A widely debated question in recent years by both strategy theorists and antitrust practitioners is what role product differentiation between firms plays in their ability to sustain a collusive agreement in order to reduce the strength of competition and gain higher profits. This paper addresses...

We consider the spatial competition between two traditional physical (or offline) retailers and an Internet (or online) retailer where the efficiency of the latter differs from that of the former. We assume consumers are heterogeneous across two dimensions: (i) the costs of traveling to either...