A general discussion covering both the common problems and features of the full range of the mass media industries, and some economic notions central to understanding them, opens this report, followed by introductory essays for individual industries and consideration of public policy issues. The basic economic considerations common to the field which are discussed include media products, monopolistic competition, and advertising markets. Brief discussions and summaries presented for newspapers, broadcast television, book publishing, and other media (cable television, magazines, and radio) touch on their technology, development, and economic structure; up-to-date statistics are provided. Characterizations of markets developed to illustrate some of the problems and possible solutions to defining media markets focus on the umbrella structure of newspaper competition in the San Francisco Bay Area and the New York City media market. The identification and discussion of perceived policy problems found in one-newspaper cities, group and chain ownership across media markets, cross-media ownership in a given market, and product distribution conclude the report. (Author/CMV)