Public and school libraries having begun as an outgrowth of each other and then separated, have some overlap in philosophy, function, and public served. Although studies have opposed the combined school and public library, communities continue to attempt mergers largely for promise of dollar savings. There is also a philosophical trend in community development to unite disparate agencies into one superagency, a community center. An examination of five libraries in Canada--Sir Winston Churchill Joint School Public Library, Coquitlam Centennial High School and Community Library, Killarney Secondary School Public Library, White Oaks Public and School Library, and Meadowvale Community Library--concludes that failures were due to differences in role definition. Problems resulting from role conflict include blurred lines of financial support; different emphases on nature, control, and housing of combined collections; differences in classification and shelving of combined collections; differences in users; and lack of community library use by the general public. Experimentation should concentrate on an institution combining social agencies and the public library with new role definitions. (Author/KP)