The number of school districts with socioeconomic integration plans has more than doubled in the past decade and the sophistication of such plans has increased. The nine district case studies from across the United States profiled in this report provide valuable lessons for school integration efforts: (1) When socioeconomic diversity policies are well implemented, they appear to produce strong academic outcomes for students and better prepare them for living in a diverse society; (2) While school integration is often politically challenging, key steps--such as the use of choice and incentives--can smooth the path to community support; (3) Setting clear system-wide goals for integration increases the likelihood of achieving success; (4) Policies that break down artificial walls between city and suburb can have greater impact than those limited to existing district lines; (5) Socioeconomic diversity policies can often lead to racial diversity; (6) Districts have grown more sophisticated in defining disadvantage; and (7) Districts are more likely to be successful when they ensure integration not only in school buildings but also in school classrooms. [Individual papers are indexed in ERIC.]