Educational policy discussions typically exclude the teacher's voice and ignore constraints of time, energy, and resources that challenge teachers and hinder policy implementation. The case studies presented in this monograph attempt to restore the teacher's perspective. Rather than analyzing policy shortfalls stemming from teacher "apathy" or "incompetence," the booklet studies three successful high school English teachers committed to their profession and to visions of "best practice" within diverse classroom contexts. A qualitative approach based on interviews, classroom observations, and examination of written documents was employed to construct the case studies. Each case study contains a description of the teacher's school day and interpretive sections examining work demands and teaching strategies. All three teachers worked at suburban, comprehensive high schools with enrollments of about 1,500. Confronted with persistent demands of curriculum management, large classes, and time constraints, all teachers studied developed conservation and isolationist strategies to ensure their daily survival. Teachers' work environments resemble other "street level bureaucracies" (like police stations and welfare offices) characterized: by (1) inadequate resources; (2) ambiguous goals; (3) unclear performance evaluation criteria; and (4) nonvoluntary clients. Fortunately, the teachers did not process their students as they did their curricula, but negotiated cooperative alliances with students and bent rules in their interest. Policymakers need to follow these teachers' example and seek alliances with teachers, develop supportive staff development programs, relinquish tight control over classroom methods, and revamp their stereotyped images of teachers. (22 references) (MLH)