Platform businesses add value by facilitating interactions between customers who are attracted in part by network externalities. Two-sided platform businesses with low costs of reversing participation status have become more important with the rise of the Internet. This essay is concerned with...

What is a catalyst? -- Build a catalyst strategy -- Identify the catalyst community -- Establish a pricing structure -- Design the catalyst for success -- Focus on profitability -- Compete strategically with other catalysts -- Experiment and evolve -- Cracking the catalyst code

This essay surveys the economic literature on interchange fees and the debate over whether interchange should be regulated and, if so, how. We consider, first, the operation of unitary payment systems, like American Express, in the context of the recent economic literature on two-sided markets,...

Software platforms are a critical component of the computer systems underpinning leading? edge products ranging from third? generation mobile phones to video games. After describing some key economic features of computer systems and software platforms, the paper presents case studies of personal...