Two related questions are investigated in this research: (1) the characteristics which differentiate those schools which extensively use educational innovations from those which do not; and (2) the factors that determine whether innovation will be a carefully thought-out and discriminating process, rather than a process primarily influenced by (and incorporating) the latest educational fads and fancies. Most of the material in the report relates a variety of independent variables to adoption of innovations in schools in major cities. Separate sections of the study establish a typology of innovations with respect to both the quality of, and the frequency with which, specific types of innovations are implemented; discuss the school systems surveyed; examine several characteristics of schools such as student bodies, community involvement, and student morale; report investigations of the relationship between the availability of both physical and staff resources and the frequency with which innovations are adopted; discuss school structure in terms of both size and complexity; and, focus on individuals involved in the schools. The final section of the study includes a summary of major findings, a discussion of the implications of these findings for policy, and recommendations for future research. (Author/JM)