This is one of several papers presented at a Federal Trade Commission Symposium on Media Concentration. Local newspaper monopolies exist in over 97% of U. S. cities. However, inevitable economic forces are not the only cause of monopoly as some have suggested. Two other contributors to monopoly have been economic practices by daily newspapers and governmental intervention in the economics of daily newspapers. While various economic practices have encouraged monopoly, combination rate structures have been especially instrumental. Combination rates are for space sold simultaneously in both a morning and evening newspaper, published by either a single owner or by two publishers operating under a joint operating agreement. The intent behind the rates not only reflects a philosophy of reduced combination costs, but makes the combination a must-buy, eliminating competition. With the Newspaper Preservation Act, Congress has created an antitrust exemption for the joint-operating agreements existing between the only two daily newspapers in 22 cities. These agreements, consisting of plant-sharing, joint price-fixing of advertising and circulation rates, and a sharing of profits, have worked to prevent entry by other newspapers into the market and have established a congressionally approved editorial voice in these cities. (MKM)