Results of a study of practices and preferences in teacher supervision and evaluation in Maryland public schools are reported. The study surveyed supervisory practices in 24 local education agencies (LEA's) through a survey questionnaire and a literature search. The report identifies 18 key findings and issues relating to supervision, including the following: (1) The larger the district, the more teachers are supervised by any one supervisor. (2) More attention is paid to the "means" of data collection than to the "end" of instructional improvement. (3) In practice, assistant supervisors, central office supervisors, and school-based supervisors rarely have a common understanding of the purpose, philosophy, and process of supervision. (4) Supervisors prefer to be independent and want to develop greater expertise in using relevant research. The study also found a wide range of perspectives, expertise, and approaches in locally developed materials for supervision and evaluation. While diversity may be appropriate, the researchers felt there should be cohesion with an LEA and stronger evidence of activity to improve instructional practice. LEA's may benefit from applying a process of interactive strategic planning, improving coordination, reducing organizational complexity, and focusing on improvement of supervision. Included are 20 tables and a 4-page bibliography. Ten appendixes provide summaries of models of supervision study. (MD)