The involvement of teachers in large-scale innovations is critical if attempts to improve schooling are to succeed. An analysis of the teacher's role in educational change is presented with particular focus upon teacher concerns about innovations. A description is given of the Concerns-Based Adoption Model, which identifies the individual teachers as the primary target of interventions designed to facilitate change in the classroom. The factors that encourage or discourage participation on the part of teachers in an innovation project are explained, and an outline is presented of the six stages of concern that teachers undergo in gradually accepting and internalizing an innovation. The important factors which emerge during the implementation stage of an innovation are explored, and recommendations are made for developing effective inservice training programs that will encourage teachers to participate in educational changes. (JD)