A renewed emphasis has been placed on mixed-income housing through HUD's HOPE VI program and the bipartisan consensus to end the concentration of low-income people in public housing. Through an analysis of seven successful mixed-income housing developments, this article concludes that successful mixed-income developments must be well located and carefully designed and managed if they are to attract renters who have location choices. Mixed-income housing works best where there are sufficient units aimed at the higher income renters to create a critical mass of market units and where there are no differences in the nature and quality of the units being offered that are due to the income of the renters. However, income mixing alone is not sufficient to provide upward mobility of the low-income residents and it is necessary to have activities that are specifically aimed at creating opportunities for them. Perhaps the biggest challenge is income integration in neighborhood settings where property management is not able to set behavioral norms.