A well established belief both in the game-theoretic IO and in policy debates is that market concentration facilitates collusion. We show that this piece of conventional wisdom relies upon the assumption of profit-seeking behaviour, for it may be reversed when firms pursue other plausible goals....

We investigate the competitive effects of spot-price contracting, in which a buyer and seller contract to transact at a future date at the price prevailing in that market at that future date (the ``spot price''); such contracts are ubiquitous in the beef-processing industry, among others. We...