Purpose: Research finds that the attitudes of principals and teachers create an atmosphere for learning, often referred to as school climate, that influences school effectiveness. Other research shows that atmospheres of trust, shared vision, and openness create positive school climate conditions. Little is known, however, about how these climates emerge in some schools and not others. There is good theoretical reason to suspect that interpersonal relationships between principals and their teachers influence school professionals' attitudes that define the broader school climate. Theories from organizational studies, social psychology, and sociology inform hypotheses about how affective, cathectic responses from interpersonal principal-teacher relationships explain variation in school professionals' satisfaction, cohesion, and commitment levels. Research Design: Nationally representative data from the Schools and Staffing Survey, 2003-04, match principals to teachers in public elementary schools. Using structural equation modeling, relational mechanisms between principals and their teachers are identified and explain positive principal attitudes. This process is then linearly regressed to explain the effects of these relationships on teachers' attitudes. Findings: Principals' relationships with their teachers affect principals' and teachers' satisfaction, cohesion, and commitment levels. Among principals, these positive work relationships improve job satisfaction, cohesion perceptions, and commitment levels. Among teachers, substantial variation is explained directly by the relationship mechanism of principals sharing expectations with their teachers. Conclusions: School professionals' attitudes form under similar organizational conditions as those of other workers. These relationships affect the schooling environment. Because of their centrality and leadership position, particular focus is paid to role of the principal in these relationships. The relationships of principals, as the school leader, strongly and directly affect teachers' attitudes, which define the schooling climate. (Contains 6 notes, 3 figures and 3 tables.)