The textbook view that cartels increase industry profits and lower consumer
welfare ignores the effects of competition in other activities. A revision
ist view shows that when cartel members compete in other activities, i.e. w
hen they semi-collude, the cartel members may be worse off and consumers be
tter off. Using a two-stage model in which the non-production activity is R
&D and is subject to technological spillovers, we show that both the tradit
ional and revisionist views can be wrong, that consumers and producers can
both be made worse off, or both better off, by a semi-collusive production
cartel.