The purpose of this systematic overview was to assess the evidence for the effectiveness of public health nursing interventions when carried out by the strategy of home visiting of clients in the pre- and postnatal period. This is an update of a larger overview first collecting literature to 1993, then updated to the end of 1995, and now updated to 1998. The search of published and unpublished literature related to home visiting resulted in retrieval of a total of 211 articles, including 149 articles relevant to all age groups and including all interventions implemented by various professional and nonprofessional groups, where the intervention was considered to be within the scope of practice of public health nursing in Ontario. When the relevance was limited to interventions where the intervenor was known to be a nurse, and the clients were in the pre- or postnatal period, there were 20 articles with quality ratings of ‘strong’ or ‘moderate’ included in this update for the systematic review, and 8 additional articles in this update. There were no reported negative effects of home visiting in the 12 strong articles. Positive outcomes included improvement in children's mental development, mental health and physical growth, reduction in the mother's depression, improvement in maternal employment, education, nutrition and other health habits, and government cost saving. There is no proven impact on low birth weight, gestational age or neonatal morbidity or mortality, although the studies had inadequate sample sizes to demonstrate a difference in such relatively rare occurrences. As a delivery strategy, nurses visiting pre- and postnatal clients in the home can produce significant benefit, particularly with interventions of high intensity and with clients who are considered to be ‘at risk’ due to factors such as low income and low educational achievement.