Three papers discuss aspects of telecommunications regulation in a deregulated environment. The first paper, "Implementing Telephone Deregulation: The Political Economy of State Regulation in the Post-Divestiture Era" (Paul E. Teske), analyzed the variation in state regulation of local telephone operating companies using regression analyses across the 50 states and comparative case studies of several states. It was found that different regulatory structures and attitudes explain much of the policy choice variation. Data are presented in four tables and a 27-item bibliography is attached. The second paper, "Network Externalities and Critical Mass in New Telecommunications Services" (David Allen), examines information services in France and Japan in order to develop a theory of the"critical mass" of network externalities that play a central role in the demand for new networks. Two appendixes, 17 footnotes, and an 11-item bibliography are included. The third paper, "A Comparison of Rate Base Rate-of-Return and Ceiling Price Regulation" (Neal C. Stolleman), uses comparative static analysis to examine two alternative regulatory systems from the perspective of a multi-output, profit maximizing exchange carrier. (Author/EW)