The study examines the relationship between principal leadership and teacher expectancy within Chicago's accountability context. Current school accountability policies assume that the threat of sanctions will motivate teachers to improve. The study uses expectancy theory, which suggests that any impact on motivation will be constrained by teachers' beliefs about their students' ability to learn and about their own ability to influence learning. Using qualitative data, the paper discusses the experiences of teachers in three schools placed on probation to understand the relationship between expectancy and leadership. The findings indicate a relationship between certain types of principal leadership (e.g., instructional leadership, support, and trust) and teacher expectancy. These findings have important implications for principals and policymakers in the current policy context. (Contains 1 table and 13 footnotes.)