Abstract
This review presents a discussion of the results of studies which have measured the effects of early day care participation on the development of school-age children. The studies are varied in their aims and methodology and they span a 40 year period of time. Although the findings are diverse it is argued that there are consistencies. For example, most studies reported some measurable effect linked to age at starting day care and most studies reported small effects for type of care experienced. Very few of the studies measured day care quality but those that do found that better quality care produced better child outcome. Some possible reasons for the consistencies and differences are discussed.