The word “hacking,” as it is commonly used, evokes images of mass thefts of information and malicious intrusions into private networks. The Oxford English Dictionary defines a hacker as “a person who uses computers to gain unauthorized access to data.” Yet the original hackers were anything but criminal. They were, rather, jubilant tinkerers, who in the face of dizzying technological advancements took “delight in having an intimate understanding of the internal workings of a system.” Although the exact origins of the word “hacker” are unclear, the most widely accepted source is the MIT Tech Model Railroad Club, which began to experiment with computers in the early 1960’s and went on to form a core part of MIT’s Artificial Intelligence Lab. This lab, in turn, was a key contributor to ARPANET, the Department of Defense-funded precursor to the modern Internet.
A hacker, in this original sense, is someone who confronts a complex system with a will to understand and experiment, to innovate and improve, and to have fun doing it. Cities, and the structural and infrastructural fabric of which they are made, are systems of the most complex sort. I coined the term ‘spacehacking’ as a conceptual framework for architectural and urban projects that seek to mediate city fabric in a range of inventive and unconventional ways. Translated to the field of architecture, it is a mode of working that entails an intimate and highly local understanding of urban, material, and social systems to enable their dynamic reconfiguration.
Over the past five years, I have worked to understand these new dynamics, studying spacehacking as a mode of production that interweaves the disciplines and practices of art, architecture, activism, and craft, first as a graduate student in architecture at the University of California, Berkeley’s College of Environmental Design, and now as a design professional in the San Francisco Bay Area. As part of this effort, I have conducted over thirty interviews with architects, artists and designers working around the world who, I argue, have fashioned themselves as spacehackers in their method of urban spatial practice. What follows are excerpts from three of those conversations, with Jan Liesegang of raumlaborberlin, Santiago Cirugeda of Recetas Urbanas in Seville, and a member of Collectif Etc, in Paris. 
The interviews articulate a range of relationships: of the temporary artifact to the more permanent built environment; of the ephemerality of a single event to the desire for lasting change; of the urban actor to their local and national context. Most of all, these three practitioners, and the larger collectives they represent, offer ways to invite new actors and transfer tools in the work of reshaping the built environment. Together, they offer a sense of the trajectory that spacehacking has traced over the past twenty years, beginning as a largely ignored and invisible outsider pursuit in Berlin of the 1990’s, re-emerging as a highly visible tool for civic activism and agitation in Seville in the early 2000’s, and transforming into an uncontroversial and even comfortable methodology in Paris today.
01 | Jan Liesegang (raumlaborberlin, Berlin, DE)
In the wake of the fall of the Berlin Wall, much of the population of the city fled for the wealthier urban centers of former West Germany, such as Cologne, Hamburg or Munich. Within and around the surplus property that resulted from this mass exodus, a culture of spatial reuse and appropriation came into being, sparking the imaginations of young counter-cultural artists and architects across Germany.
A native of Cologne, Jan Liesegang moved to Berlin to study architecture in the early 1990’s, lured in part by this insurgent spatial culture. In 1999, Jan, along with three collaborators, co-founded the design collective raumlaborberlin; in the past sixteen years, the group has grown to seven partners, and realized numerous projects around the world, without ever losing sight of their initial impulses. "How," he asked in a recent publication, "can you put people, who would normally never have the opportunity to shape space, into a position to do so?" This regard for the dynamics of participation is central to their work, whether by simply challenging the assumptions of visitors, at a temporary hotel that they constructed and occupied in front of the now vanished Palast der Republik in former East Berlin, or by directly engaging local youth in the design and production of street furniture.
Shortly before we spoke, raumlabor realized one of their more ambitious works to date: Die Grosse Weltausstellung, or The Great World Fair: The World’s Not Fair, a counter-cultural response to the trope of the architectural expo, in which a number of local designers and artists were given the opportunity to conceive and construct fifteen pavilions within Tempelhof, a former airfield situated in the middle of Berlin. The vast space is presently used as a park, though it has undergone almost no renovation since its prior life. The Weltausstellung aspired to address the immensity of its site, not through a corresponding largeness of scale, but instead through the aggregation of small moments or nodes. The work of contributors to this intervention varied widely: installation art within a previously existing bunker; a large multi-story scaffolding structure for immersive theater; a festival center with a working bar; and a highly programmed symposium space. Despite this range of interventions, the works were united in their attempts to activate the spaces of Tempelhof as they found them. They created hybridities: new interventions enabling and encouraging activity within an aging superstructure.
Excerpts from the interview:
NJ: How did raumlabor get started? Your practice is unconventional and there are a lot of partners doing very different things.
JL: The way raumlabor developed has a lot to do with Berlin and the fall of the wall. We started as very good friends—we all came to Berlin shortly before the wall came down, and then suddenly we found ourselves in this city which was a little bit out of control, you know? While we were studying we did some, what we now call urban interventions, but this term didn’t exist when we were doing them in ’95. But there were a lot of open spaces and possibilities and uncertainties.
And then after we all graduated, we just saw that what we were doing in our spare time in our little studio was so much more fun and interesting than what we were asked to do in those boom years [of the mid 1990’s] when we were working as architects. So we kept our studio, which was in Mitte, in a very central space, first to do some competitions, but also as a kind of a gallery and a space for discourse. It slowly developed from a group that was interested in public space, in occupying houses, in this whole idea of squatting.
Also, we always had happy hour, where we would invite some people to give a lecture and at the same time have this very informal bar and conversation, which led, over the years, to us getting more and more into this field, and getting recognized. And then we started to make a bit of a living out of it, and it became more and more like a real profession for us, doing what we were interested in. And this is still what keeps us together.
We’re not really a company, though; we never actually manage to make enough money to really build a company. It’s always kind of a struggle. We still try to keep everything on a level that we can do these kinds of low budget projects, so that we don’t build up this big structure. It’s good and bad.
Good and bad, how?
I mean the good part is that we have a lot of freedom, and very often we get commissions from people who just have a problem. Like maybe there’s a space in the city which is terribly neglected, and people want to do something about the space, but they’re not town planners or architects or builders, so somehow they find us, and they ask if we can do something.
And so we start developing ideas together, but it’s often very open, and we have a lot of freedom in what we propose. We have very supportive clients, which is hard to find in the normal architectural field, where everything has to pay back on a very straight economical level.
In terms of relevance for the city, it’s a bit frustrating. We have worked in the field of public space, trying to make the city more livable, more of a special place, more interesting. We have done a lot of strategic proposals, [looking at how cities can change the way they think about building, and growth, and their interactions with their citizens], and we’re still working on this small scale, and I think that’s maybe the part where we still need to develop.
Now there is all this interest in public space and there are biennales for urban interventions. I think it’s a zeitgeist that is out there, which has maybe been supporting us, and we’re part of this kind of movement, and it would make me very happy if this were more translated into new kinds of town planning tools, new tools for participation.
Some of our work, like the work we did for Tempelhof airport, already has this link between the off and the on, between the formal and the informal. So I think this is quite interesting for us right now, to find this link, to become more responsible. On a political level, I think we feel it’s time to get out of this cultural comfort zone, and it’s time to get into the real political discourse, time to take responsibility for our city and our desires, for how we run the city, or our living conditions. To really talk about: how can you view the street differently, how can you organize property differently, how can you organize space differently, so that it’s more flexible, less driven just by commercial interests, less by value, less about payback.
I mean, it sounds very abstract, but all this is just convention: what you do in public space, how you make it, what is legal, what is illegal, it is all just conventions, which I think have to be negotiated.
I was fascinated with Tempelhof when I went to visit the World’s Fair. When you guys made your first proposal, to simply open it up as a park without renovating it, what did you think would happen?
It’s such a weird place. Nobody expected it to work like [it does]! This is something where [several years ago] we were proposing just to open it, but we weren’t sure, when we said, “Yeah, let’s just open it! We have no money? No problem, just open it! It’s there, people can come and look at it.”
But we didn’t really expect it to have 20,000 visitors a weekend! We didn’t know that people from the neighborhood would just accept it as a park, would say, “Ah, it’s a beautiful park, let’s just go there.” You know? Let’s go BBQ, let’s windsurf, let’s do sports…It’s like… each of these windsurf boards is like a folly in a park, you know? They’re beautiful, they move…
You said earlier when you were talking about the good and the bad parts of your work that you would like to see new tools for participation develop. What are these tools?
Maybe I can give you an example—almost a year ago we developed an idea for what we call micro factories. A few years ago, we started to make self-built furniture for public space for a few projects, which came out of a very pragmatic situation: we were doing a lot of projects in public space, where people would come together and build kind of temporary communities, so this always involved some kind of event where you would sit down and have dinners or talk in public space.
So you would always rent these normal beer garden benches, and we started to think about: how can we do something else, how can we find a tool that people can build this furniture themselves? And then [the furniture] would stay, and create a possibility or a problem: you have all these chairs, suddenly on the square.
And because they were all participative projects, we found the educational part of it more and more interesting. In many of the difficult neighborhoods that we work in, doing something together, building something together, has such a strong impact on the community; it’s so self-promoting. If you start building something very fast, people suddenly get the idea that change is possible.
So you do some kind of fabrication, which normally only happens in factories, in public space, in very different conditions. We sort of said, “How can we put this together?” This is where this idea of learning and teaching comes in - there are [architecture] students participating, and then there are people from the neighborhood. So there are creative people who have potential, but rarely have the chance to do something in the real world, and then there are the people who have a lot of time. So these groups, they could produce these micro-factories in public space.
And we’d always try to connect local potentials—maybe someone who is really good in repairing washing machines could be in that workshop in public space, and then there would be some creative people, like our students, also trying to maybe do something more with these washing machines, and then people from the neighborhood who find out [and say], “Ah, there’s a possible business!” Because if people are in a very tight, difficult situation, there has to be some profit. So we’re trying to put this all together, but this is quite a big project, so it is hard to realize under pure cultural [funding] conditions. This is an idea that we’re already carrying around for more than a year, and we haven’t found a single slot of time or any extra money to invest in developing it. We’re kind of carrying these ideas around the world, hoping [we’ll find] one project big enough to make a prototype.
So this is the kind of thing where I think, “Ok, maybe we have to either settle down in some kind of institutional framework, maybe in a school, where you can support or develop this kind of thing, or we have to maybe find a more permanent kind of laboratory structure, which has not only project support but some kind of general support to invent and develop prototypes.” There’s a lot of these lines of inquiry that we’ve developed in our work, where we always think, “It would be so great to be able to do this perfectly, even just once.”
02 | Santiago Cirugeda (Recetas Urbanas, Sevilla, ES)
Santiago Cirugeda began creating temporary urban interventions in 1996, only a handful of years after raumlabor. However, unlike the case with raumlabor, rather than building on an opportunistic interaction between vacant spaces and governmental vacuum, Cirugeda’s point of departure was to create such spaces within the byzantine bylaws that held sway in his native Seville.
Beginning his practice amidst a series of protest movements taking place across Europe in the early 2000's, Cirugeda created Recetas Urbanas, or Urban Recipes, a collective for activist design, construction and civic disobedience. In doing so, he pivoted towards an explicitly participatory model, and developed a more aggressive stance with respect to municipalities. At the same time, he also began to question the value of temporary interventions and ‘event urbanism’ that were driven and directed almost exclusively by architects, artists, and designers.
By late 2012, when we spoke, public sentiment in Spain had reached a crescendo of discontent that amplified and made prescient Cirugeda’s positions. As one of the European countries hardest hit by the economic crisis, Spain was unusual in that it suffered not only at the hands of over-confident borrowers and negligent lenders, but malfeasant public officials, who commissioned civic extravagances contributing to the bankruptcy of many municipalities. Educators began to speak of a “lost generation” of Spanish architects, as work in the architecture, engineering and construction fields ground to a halt.
At the same time, adults across the country were moving back in with their elderly parents, unable to support themselves or their families. The Spanish equivalent of Social Security became a primary source of income for these citizens. An estimate published by the Guardian in late 2014 noted that up to 500,000 partially constructed properties had been abandoned since the onset of the crisis while hundreds of thousands of people were forced from their homes, in both cases leaving behind fallow land and empty structures. In this charged atmosphere, Cirugeda’s actions took on new urgency.
Like raumlabor, Cirugeda began to apply the tactics he developed through his work with small urban interventions to larger civic questions. I interviewed him in La Carpa, the physical instantiation of one such effort. La Carpa is a community arts compound on illegally occupied (but previously vacant and neglected) public land. La Carpa brought together an array of Recetas Urbanas’ previous interventions: “El Chimpum,” “La Oficina Araña,” and “Aula Abierta,” among others.
Excerpts from the interview:
NJ: Tell me about how you started working in this way—because you started in a very unusual way, I think—and also what is important to you about your particular way of working?
SC: At the beginning, in 1996, I remember my first project… I was a simple citizen. I didn’t have the title of architect: I was an artist, a citizen, a neighbor, who decided to use public space. And at the beginning I was afraid, really, because my family is all in the military: my father, my brother, my grandfather. So my culture is very rigid, no? Really!
So when I began to propose a project in a public space, I thought, “Ok, it could be illegal, so I have to check what’s happening with the law, with the regulations.” I began to study, alone, how to use public space within the law, and I began to pay for simple permits to use scaffolding or dumpsters, in a legal way, because the use never appeared in the law.
“You can’t sleep inside scaffolding! You can’t live there! You can’t put a playground on top of a dumpster!”
It was amazing, because each week for six months, I brought my money from working in bars and said, “Ok, I want to fight with my politician.” It was a political question, really. But totally alone. I was studying architecture, but I had no team, no group, no collective. It was very important to discover that, as a citizen, you can offer, you can propose.
For me, it’s very important to think about public space in terms of regulations: administrations and politicians try to control it, but you can make different things. Like here: we haven’t any license to build! All this is built ourselves. All of this! With wood from Madrid, a building we brought from Granada—it was built seven years ago with many people in Granada, but six years later we said “We need this, here!”—so we brought it from Granada!
This building we’ve had for only two weeks! We made, not business, but an agreement with a very poor firm, a container service in Seville. They have no work, no money, so we said, “Give us two of these, free, ok, without any money, and we will build a work center for your guys.”
It shows that in crisis, people can invent space.
And so this space, the ground, who owns it?
The owner? The owner is the City of Seville! So it’s happening! Our fight is with the city or the planning office or the politician, because it was not like this (gesturing)—it was empty! An empty place, dirty, so we said, “If you don’t want to be responsible for this public space, we will propose a different way, a different system!” To use the public space and offer it openly, because it never appears in the urban plan of Seville what to do here! It doesn’t appear!
“Let us invent here!”
It’s a weird position, because many times I’ve used streets or [vacant] lots in a very fast way, dumpsters and scaffolding and illegal action, and I don’t know why, but now I prefer to show that we can make it for longer. Not always four months, six months. No! Eight years! It’s another type of fight. It’s longer. For me, it’s heavier.
For me, the short things are [great] because you can be very fast, so the police, if they come to you, you can react in no time. [They aren’t going] to change the world, [they come from a] feeling of “Fuck you! We will stay here!”
So the short things, the small actions, they make a point.
Yes! When we went to a political meeting with the mayors of Madrid and Seville, at the end, we said, “Pffff, totally boring.” So, the next week [I made] a short action that appeared in the newspaper, and said, “Ok, you remember our meeting? If you want, I can return to making short things. If not, we can try to make another type of covenant, that’s not a disaster.” So it’s a question of saying, “We can!” Of saying, “Remember, I put a tree in your house. I put scaffolding in your face. So, take it easy.”  It’s a question of power. If you say fight, I will fight you! I don’t like to fight, ever! I hate it! But it’s the only way… It’s the only way…
And is there space for form, or aesthetic? As an architect, how do you think about these questions, how do you make decisions about them?
I never decide the design! I prefer to have problems with the politicians, not with my people, with friends. I say, “What do you want?”
Then they say, “Help me, no?” and I say, “No, I have my problem with the politicians, fuck you and your problem!” It’s the joke, always…
“But we make everything together!”
“No, but not now! That is your project, and your problem, ok! It’s beautiful. But fuck you, it’s your project.”
It’s a joke, ok, but it’s the same. And we change… at the beginning, when I was alone, I would go, very proper, “I have a meeting at 11 with the Mayor, with the architect…” So then they would fuck me, because you arrive alone, one person, and they are five: a lawyer, an architect, the politicians, the secretary, their mothers. You say, “I am thinking about…” and they say, “No, the law has changed.”
“Are you sure it changed? The plan says it’s possible to make a covenant…”
“No, we have a covenant like this.”
So now, the important meetings, we come with ten people. Lawyers, hackers, and all. It’s a question of methodology. I’ve changed from a citizen to an architect to Recetas Urbanas, and now, to a network. This is the question.
03 | Le Collectif Etc (Paris, FR)
Le Collectif Etc formed in 2009, when a group of students and recent graduates from the Institut National des Sciences Appliquées in Strasbourg were given the opportunity to repurpose an underutilized parking lot in front of the University’s main building. In that initial project, titled Á nous le parking, or We have parking, Collectif Etc developed a project where students at the school designed mobile, temporary public furniture and amenities based on standard shipping pallets. It was so successful that the school administration decided to make it permanent. This is the essential model for Collectif Etc’s practice—open participation, self-building, and working under the umbrella of an existing authority.
Building upon this collaborative approach, in 2012 several members of Collectif Etc embarked upon a twelve-month tour of France by bicycle, entitled Détour de France. Their objective was to literally place the work of Collectif Etc into context with a larger movement towards temporary urbanism that was gathering momentum amongst young activist designers in France, an effort made possible by France’s generous unemployment policies and the pooling of the group’s financial resources.
Excerpts from the interview:
NJ : How did Collectif Etc start? Was it when you were still in school?
CE: Yeah, we were just a group of friends from two classes. When we started, we were doing street art. We would say, “Ok, let’s meet this Sunday and do something.” without much idea of what it would be.
One day we decided to work on a wall that had these fake windows, and do stuff on them. And many people came to help us—people from the buildings around, who said, “Oh, maybe you need this tool,” or, “Could we help with that?” or, “What are you guys doing?” And it was great. It was really nice for everyone, and by the end of the day we said, “Ok, what matters is that people get involved. That’s how it’s interesting for us, and interesting for them.”
As architecture students we got to study many things, but we missed one thing, which was to build real-scale stuff that we had designed. So we offered to organize a workshop for students [at our school] to build furniture for a parking lot that’s right in front of the school. There was no public space where students could stop a little bit and smoke cigarettes, or eat something. So we said, “Ok, let’s remove all the cars from this parking lot and put them in a parking lot that is behind the school and always empty.” And the school said, “Ok, you’ve got a couple of thousand euros, you can buy some materials and organize this, go ahead.”
So we did these pieces of furniture that people can move, and the students designed them, and built them, and we were all around and all working together, and it was great.
I love that project! The pallets are such a basic form, and the furniture itself is super rough, but the activity that you managed to create was really remarkable.
Oh, you know it! The school really loved it also, and decided to make it permanent! So we thought, “That was a good start, and we got some good publicity from it.” And we applied to a competition to design a public space in Saint Etienne. When the jury was happening, we said, “If you pick us, you have to know that you have to let us manage all the money, and you have to realize that we will do a collaborative, participative work with all the inhabitants. That’s what we stand for—if you don’t accept that, we don’t want to win the competition.” And they picked us.
When some of us went to St. Etienne to prepare, we already had in mind this idea of the Détour, taking one year off to go around France, meet all the people who work in the field we work in, create a network between these people, and see if we could actually exist and survive. We had two goals: one was meeting all these people, and the other was to work with them, create projects, and build stuff.
So you made a lot of projects as you went…
Yeah, we did around 15 projects, or something like that. It was great: we met and worked with so many [people] from different fields, with different interests. We worked with municipalities and associations, with schools, with social centers, with random people. We worked in the center of cities, and we worked in neighborhoods outside of cities, in rich places, poor places. We worked in villages…
It was really amazing, and the response from everyone was great. Because politically, no municipality can say no to somebody who comes and says, “Ok, I’m trying to legitimate [taking] an action in the public space [with your citizens]: do you accept that or not?” They can’t say no, or they will lose votes for the next election.
It seems to me that right now it is in France, more than in almost any other place, that there is this type of thought or engagement. There are so many collectives active here. Do you have some insight as to why this is happening here, now?
I would say that by the late 90’s, there were a couple of groups who appeared out of the blue, Bruit du frigo, and Coloco and Atelier d’ Architecture Autogeneré, and they fought for things, and they are still alive now. I mean, many of them [have since] stopped, but they were the first group of people who said: it is possible. This is what we believe in and it is possible.
It was not fashion then, it was not really what it is now: now it is trendy to work in this field, I would say. So there was a moment then, and nobody heard much about it, but now the trend is social - it’s easy to communicate with people, it’s easy to get collaborative tools. So these tools, and the fact that the background was already there [in France], I think explains the fact that we just appeared and that so many groups such as us are…
… appearing all at once.
Right now, yes. We’ve been meeting all these people, we interviewed like thirty groups [on our trip], and we are creating a platform where the experiments we’ve been doing will appear. The aim is to show and to explain processes, to make them legible to the people who can make decisions. We want this not to be our product, but the product of the whole community of people, a tool that everyone can be involved in and everyone can use.
Are you thinking about what happens next, how it evolves?
Well, we think it’s not enough to talk to people – we think it’s better to do things together. In Bordeaux, we worked on a public square; we did these workshops every day where people could come and saw wood and we had nails, screws, whatever.
But then, this is not for everyone. This is for people who are interested in [building things]. So we believe there should be food lessons, there should be music, a concert, there should be round tables – that’s really important, actually – and there should be petanque competitions or whatever, to make sure that everyone can come and talk about what matters. And what matters is living together in a place. We believe that the city should evolve as people evolve, and that means all the time. Temporary interventions are a way to show that with little money, much ambition and many people, you can do great things.
Reflections on the practice of spacehacking
Hacking is both a conceptual apparatus and a set of skills and tools that facilitate engagement and reengagement with a shifting urban landscape. Foremost amongst these tools is the ability to construct experiments that test new ideas and techniques. Spacehacking consists of real-time testing of physical structures and material systems, as well as social structures and modes of engagement.
Practices of spacehacking—temporary interventions, urban prototyping, tactical urban actions —which were launched to prominence with the worldwide financial crisis of 2008 and embraced by a battered civic-industrial complex, now face scrutiny, as cities, markets and practitioners once again embark upon large-scale, long-term projects. A wider array of actors is beginning to ask many of the same questions as Jan Liesegang and his contemporaries: what is the efficacy of the intervention as a tool? What is its ability to effect lasting change in a city? How can tools being pioneered at a micro level—technological, material, and social—scale up?
It is clear that urban interventions must either continue to evolve in order to move towards answers to these questions, or risk irrelevance. Having made the journey from architectural and political non-entity, to adversary, to useful ally for the market and civic forces that shape our urban spaces, they face a new struggle: avoiding cooptation by the very things they were protesting. Already, pioneering urban interventions like Platoon Kunsthalle in Seoul and Berlin and PROXY in San Francisco face corporate imitation in the form of projects like the BoxPark in London, which at the time of my visit in 2012 featured storefronts for The North Face, Oakley, Beats by Dre, and Lacoste, or the The Yard at Mission Rock in San Francisco, a near-replica of the PROXY project undertaken a few miles away at the behest of the San Francisco Giants baseball team.
This burgeoning use of temporary spaces and events as outreach tools by development corporations points towards a widening awareness of the real value of spacehacking in exploring the latent potential of urban spaces, and in helping to reshape their narratives within the social fabric of a city. The challenge for spacehackers, going forward, is to stay at least one step ahead.
 Hacker, Oxford Dictionaries, Oxford University Press, accessed March 19, 2015, http://www.oxforddictionaries.com/us/definition/american_english/hacker.
 For the definitive history of the original hackers, see Steven Levy’s Hackers: Heroes of the Computer Revolution (New York: Anchor Press, 1984).
 As defined by G. Malkin, in an early glossary of Internet slang, “Network Working Group: Request for Comments 1392”, IETF.org, accessed March 19, 2015, https://tools.ietf.org/html/rfc1392.
 Many of these interviews were conducted with the generous support of the John K. Branner Traveling Fellowship from the CED at UC Berkeley, which provides for one year of global travel and independent study.
 All interviews included here were conducted in English, with the exception of the conversation with Santiago Cirugeda, which was conducted in a mix of Spanish and English and translated by the author for this publication.
 An early and brief examination of these pioneering interventionists is Peter Arlt’s, “Urban Planning and Interim Use”, Temporary Urban Spaces: Concepts for the Use of City Spaces, eds. Florian Haydn and Robert Temel (Basel: Birkhäuser, 2006).
 Raumlaborberlin, Acting in Public (Berlin: Jovis, 2008), 54.
 Large-scale protests were a recurrent phenomenon in Spain at this time, a response to a neoliberal shift in economic policy. On March 16, 2002, protests in Barcelona, saw nearly 500,000 people take to the streets during an E.U. Summit moving towards freer markets within the Eurozone. Another notable protest during this period was the global Anti-War Protest on February 15, 2003, which was attended by up to two million protestors in Madrid, and one to one and a half million in Barcelona. https://www.globalpolicy.org/protests/30952-anti-globalization-protest-barcelona-march-15-16-2002.html
 Daniel Fernández Pascual & Alon Schwabe of Cooking Sections (cooking-sections.com) offer the most “edible” explanation of the particularities of the Spanish economic crisis through their performance/lecture “Geopolitical Paella”, featured in the 2014 US Pavilion at the Venice Biennale of Architecture as part of the OfficeUS collaborative project.
 The effects of the economic crisis on the architectural profession in Spain are hard to overstate: by one account, the number of housing projects built dwindled from 920,000 in 2006 to 60,000 in 2011, forcing up to 45% of architecture firms to close their doors. David Cohn, “The Pain in Spain,” Architectural Record, August 2012.
 Ana Naomi de Sousa, “How Spain’s ‘guerrilla architect’ is building new hope out of financial crisis,” The Guardian, August 18, 2014, accessed March 19, 2015, http://www.theguardian.com/cities/2014/aug/18/santiago-cirugeda-guerrilla-architect-spain-seville-financial-crisis. One of the most remarkable reactions to these abandoned development projects is the Campo de Cebada in Madrid (http://elcampodecebada.org/), which has been a probing ground for several design collectives, as well as a self-governing and much-loved resource within its community.
 Both are references to two punitive urban interventions undertaken by Recetas Urbanas as part of disagreements with city officials.
 A profusion of such design groups organized as egalitarian and participatory collectives came into being during the European financial crisis; in Paris alone, that list encompasses Bellastock, Atelier/TRANS305, YA + K, and EXYZT
 While conducting interviews in Paris, I was hosted by members of the participatory design collective YA+K (http://www.yaplusk.org/); I was also introduced to or interviewed individuals associated with several similar groups, including Atelier / Trans305 (http://www.trans305.org/), Bellastock (http://www.bellastock.com/), aaa (Atelier d'architecture autogérée, http://www.urbantactics.org/), and Coloco (http://www.coloco.org/).
 Within the last several years, a number of new curatorial efforts have been directed at work in this vein, including publications such as Peter Bishop and Lesley Williams’ The Temporary City (New York: Routledge, 2012), Philip Jodidio’s Temporary Architecture Now! (Cologne: Taschen, 2011), and a+t 38: Strategy and Tactics in Public Space (Vitoria: a+t architecture publishers, 2011) and marquee exhibitions around the world, including Spontaneous Interventions, the U.S. representation at the 2012 Venice Biennale of Architecture and Uneven Growth: Tactical Urbanisms for Expanding Megacities, currently on view at the Museum of Modern Art in New York.
 Skepticism about the long-term usefulness of temporary interventions was a theme that recurred in my discussions with a number of early advocates of the medium.
Nathan John is a designer, writer and visual artist based in Oakland, California. His current work leverages the ethos and techniques of the hacker/maker movement and the material palette of the architectural avant-garde in testing the potential of small, temporary interventions to reorient our perceptions of urban environments. He holds a Master of Architecture from UC Berkeley’s College of Environmental Design, where he received the Eisner Prize in Architecture; he has also been the recipient of the John K. Branner and Thomas J. Watson Traveling Fellowships in support of his research on urban public spaces and their activation.