Many of these studies focus upon the tension between the two kinds of “fixes” – that which is perpetually seeking to resolve the crisis tendencies of capitalism (overaccumulation) through the production of space (consider, as an example, the key role of suburbanization in the United States after 1945 in absorbing surpluses of capital and labor); and that version of the fix which is about the tying up and the pinning down of large amounts of capital in place through the production of fixed and immobile capital in the built environment (e.g. the highways systems needed to facilitate suburbanization).