We propose a general model of monopolistic competition, which encompasses existing models while being flexible enough to take into account new demand and competition features. The basic tool we use to study the market outcome is the elasticity of substitution at a symmetric consumption pattern,...

Incorporating space in economic models has two important consequences. First, the hypothesis of perfect competition becomes untenable, and second, the distinction between private and public goods becomes blurred. We review arguments that lead to these conclusions and summarize recent work...