In this chapter, we seek to understand key economic consequences of network effects. First, in Section 3.1, we analyze the impacts that network effects have on the demand for participation on a platform. The main lesson we draw is that the interdependence between individual demands leads to unconventional aggregate demands; in particular, we show that a given price for accessing the platform may be compatible with several levels of participation. Next, in Section 3.2, we explore the pricing of access to a platform, which is made complex by the presence of network effects. Finally, in Section 3.3, we discuss other strategic decisions that platforms need to combine with pricing to manage network effects; in particular, a platform has to decide the extent to which its services are compatible with alternative services.