What if the constraints and limitations of architecture became the catalyst for design invention? The award-winning young architecture firm Lewis.Tsurumaki.Lewis calls their answers to this question 'opportunistic architecture.' It is a design philosophy that transforms the typically restrictive conditions of architectural practice—small budgets, awkward spaces, strict zoning—into generators of architectural innovation. Lewis.Tsurumaki.Lewis presents a diverse selection of built and speculative projects ranging from small installations to larger institutional buildings. Built projects are accompanied by thought-provoking texts, beautiful drawings and photographs. An appendix distills their design philosophy into five tactics, a readymade code for students and practitioners looking for design ideas for the real world. Lewis.Tsurumaki.Lewis is an architecture partnership established in New York City in 1997 by Marc Tsurumaki, Paul Lewis, and David J. Lewis. Paul Lewis is Assistant Professor at Princeton University. Marc Tsurumaki is Adjunct Professor at Columbia University. David J. Lewis is Associate Professor at Parsons The New School for Design.