There continues to be a great deal of debate about the role that field experiences play in teacher development and about the relative contribution of various individual and institutional factors to the socialization process. Field experiences in teacher education entail a complex set of interactions among program features, settings, and people (the ecology of field experiences); research which seeks to understand the role of these experiences in teacher development must reflect, in its conceptualization and methodology, the dynamic and multidimensional nature of the event being studied. If one accepts this ecological viewpoint, then it becomes necessary to understand the influence of various interacting factors to understand the influence of any given factor. An understanding of three specific elements of this ecology is a necessary ingredient in studies of field experiences: (1) structure and content of field experience programs; (2) the characteristics of placement sites; (3) characteristics, dispositions, and abilities of individual students and their "significant others." The conceptualization of "development" in these studies needs to be broadened to include the documentation of actual actions and interactions and the investigation of unanticipated outcomes. (JMK)