In the latter part of the C20th, a series of seminal books were written which examined Los Angeles by the likes of Reyner Banham, Mike Davis, Edward Soja, Allen Scott, Michael Dear, Frederick Jameson, Umberto Eco, Bernard-Henri Levy, and Jean Baudrillard which have been hugely influential in thinking about cities more broadly. The debates which were generated by these works have tended to be very heated and either defensive or offensive in approach. A sufficient amount of time has since passed that a more measured approach to evaluating this work can now be taken.The first section of this book, 'Contra This and Contra That', provides such a critique of the various theories applied to Los Angeles during the last century, balancing the positive with the negative. The second part of the book is an investigation of L.A. as it exists on the ground today. While political, the theoretical stance taken in this investigation is not mounted as a platform from which to advocate a particular ideology. Instead, it encompasses cultural as well as economic issues to put forth a view of L.A. which is coherent and cogent while at the same time considering its multi-layed, complex and ever-changing qualities.It concludes by arguing that sectored off and 'totalizing' visions of the city will not do as instruments of urban analysis and that only a theory as mobile as its target will do: one that replicates the polymer nature of this place. It proposes that, extending that theory to the world beyond this particular city, only a theory that models itself on the mobile and polymer nature of the world, while still retaining a sense of the actual and the real, will do as an instrument with which to comprehend the world. In doing so, this book is not only a model by which to think through Los Angeles, but as a model by which to thinkthrough other world cities.