"High Schools That Work" (HSTW) is the oldest and largest of Southern Regional Education Board's (SREB's) several school improvement initiatives (which also include "Middle Schools That Work"). The central purpose of HSTW is to engage students so fully in their learning that they stay in school and complete a rigorous, relevant curriculum that prepares them for a successful transition to post-secondary studies and/or the world of work. HSTW is a reform model shaped by these beliefs: (1) Most students can master a rigorous academic and career/technical curriculum and should have access to such a curriculum; (2) Greater gains can be made for students when educators adopt an "effort-based" focus rather than an "ability-based" focus; and (3) Teachers and school leaders have the capacity to create an environment that motivates students to make the effort necessary for success. Begun in 1987, HSTW is currently being implemented in more than 1200 sites across the United States. SREB supports the schools with technical assistance, professional development, and data analysis. Thirty-two states have chosen to become "HSTW States," entering into a consortium with SREB and agreeing to develop and maintain a state support network for schools implementing the initiative. Implementation of this comprehensive reform initiative is guided in each school by a clearly articulated framework of goals and key practices summarized in this paper. (Contains 8 online resources.)