From the perspective of competitors, competition may be modeled as a prisoner’s dilemma. Setting the monopoly price is cooperation, undercutting is defection. Jointly, competitors are better off if both are faithful to a cartel. Individually, profit is highest if only the competitor(s) is...

The conventional view that product heterogeneity limits the scope for collusion among oligolpolists has been challenged in recent theoretical work. This paper provides an argument in support of the conventional view by emphasising the role of uncertainty. I introduce the idea that, with...