As of May 2015, 174 GH homes were in operation, 80 percent of which provided long-term nursing care. These homes have elicited great interest among policy, provider, and research stakeholders, in large part because they offer a true alternative to traditional models of nursing home care and are consistent with the "culture change" movement by focusing on person-centered care and deinstitutionalizing the nursing home (Koren 2010;Zimmerman, Shier, and Saliba 2014). At the same time, the cost of new construction for GH homes has become a point of concern ( Jenkens et al. 2011) as have questions about whether outcomes are at least comparable to traditional nursing homes in which nurses and allied health staff are more readily available (i.e., in the GH model, the clinical care staff is available but not based in the GH home itself; Zimmerman and Cohen 2010).Between 2011 and 2014, the Robert Wood Johnson Foundation funded an independent evaluation of GH nursing homes by four project teams; their collaborative interrelated research projects examined GH care processes and outcomes. Termed the THRIVE Research Collaborative (THRIVE: The Research Initiative Valuing Eldercare; Fishman, Lowe, and Frazier 2016), these projects collectively constitute the largest and most coordinated evaluation of the GH model to date, and they are described in this special issue of