This report provides the results of a comprehensive 4-year study of a statewide instructional improvement effort in Maryland; presents the characteristics of successful staff development for each of four implementation strategies (active teaching, mastery learning, student team learning, and teaching variables); and identifies the relationships among key elements of planning, training, and classroom application. The staffs of eight local education agencies (LEAs) participated as they implemented instructional improvement. Each year, data collected through documents, observation of classroom teaching, local workshops, and questionnaires were analyzed to identify the most successful project(s) for each of the four implementation strategies and to determine the characteristics of staff development efforts that influenced project success. The bulk of the document consists of summaries of eight projects (two per implementation strategy) that were identified as successful in terms of instructional gain; scope and intensity of implementation; fidelity of implementation in reflecting the developers' intentions; cross-hierarchical harmony; fulfillment of contracted responsibilities; and indication of project institutionalization as state funding ceased. (LL)