While most instructional supervisors recognize the importance of mutual trust and collaboration in building effective interpersonal relations with teachers (involving high cooperation, mutually agreed upon goals, and demonstrated positive outcomes), supervisors' attempts to achieve these ends often prove frustrating. This paper examines factors promoting trust, barriers to trust, benefits and methods of building trust, and staff development activities to promote schoolwide trust. To empower teachers to view themselves as managers in charge of school productivity, supervisors need to demonstrate trust in teachers, acknowledge the importance of teachers' role, and show their willingness to build collegial relations with teachers based on equality and mutual regard. Trust is related to several factors: the purpose of supervision and evaluation; confidentiality; handling of complaints; consistency, honesty, and sincerity; and collaboration and participation in the supervision process. Barriers to trust include teacher distrust and anxiety concerning evaluation, teachers' hesitancy to express problems and concerns, supervisors' managerial styles, and time constraints. A major benefit of trust-building is to assist teachers in self-evaluation and in addressing problems before they become major. Supervisors can also help teachers brainstorm solutions to problems. Successful organizations function by encouraging their members to collaborate on strategies for improving organizational effectiveness. Appended are 11 references and workshop materials, including suggested readings, geared to building trust in teacher supervision and evaluation. (MLH)