Purpose: This article presents an overview of what is known about dementia services in assisted living settings and suggests areas for future research. Design and Methods: We undertook a search of Medline, the Journals of Gerontology, and The Gerontologist. We then organized publications dealing with the target subject into 10 topic areas and reviewed them. Results: The article describes the demographic characteristics of cognitively impaired residents in assisted living and related residential settings in the United States, the services they receive, and process and structural elements both in specialized dementia units and in integrated assisted living settings. Finally, we review the literature on methodological issues regarding research in this area. Implications: It is important to generate research on processes as well as outcomes, such as dignity, individualized and pleasurable experiences, and freedom from pain and discomfort. We make recommendations for both content areas that would benefit from further research as well as methodological approaches that will yield important information in this field.Key Words: Long-term care, Alzheimer's disease, Cognitively impaired, Aging in place, Residential careThis article outlines what is known about dementia services in assisted living settings and explores the many questions that remain unanswered. Ultimately, research is needed that will offer specific information regarding how assisted living processes and structure result in specific outcomes in the various subpopulations of cognitively impaired residents. The variability of assisted living and its philosophy of customizing services to the wishes and needs of each individual resident provide a rich environment for research as researchers attempt to discover what works best for whom (Feldman & Kane, 2003). We also discuss the range of processes and outcomes that one should consider in evaluating the effectiveness of assisted living services and environments, including the central role of quality of life in the assisted living philosophy of dementia care.Assisted living, as an industry, is less than 20 years old. Early research sought to enumerate how many people with dementia lived in assisted living, how many were in special care units (SCUs) or in general assisted living settings, and what kinds of services they received. However, even these simple facts have been elusive as basic data such as the prevalence of dementia can be difficult to determine in these non-health-care settings. In fact, determining which settings meet the criteria to be considered assisted living can, in itself, be less than straightforward.Central to the assisted living philosophy is a respect for the individuals who live in this setting and their continued rights as citizens and human beings. However, this philosophy is challenged when the people served have cognitive impairments that compromise their ability to make or communicate decisions regarding their care and lifestyle choices.Not all regulators, providers, family members, co...