This article traces how the work of instructional leadership in the urban high school embodies a response to particular pressures in the school's environment. Based on evidence from multiple-case study research in four urban districts, the article demonstrates how supervisory and nonsupervisory leaders fashioned responses to the district (and state) system of instructional guidance and support, accountability, and the press for data-based practice. The analysis shows that in schools that display evidence of progress on a learning improvement agenda, the responses to environmental pressures reflect active engagement with what the environment offers, rather than the reactive compliance that can so often accompany reforms that emphasize high-stakes accountability.