The health and development of a group of children aged 3-7 years born to and reared by mothers who abused opiates when pregnant and who remain on methadone maintenance was compared to a group of age and socially matched control children. There was no difference between the two groups in terms of health and development although the children whose mothers were on methadone had smaller head circumference measurements than the controls. More than half of the index children had been on the child protection register during infancy; all but one were off the register at the time of the study. The results suggest that drug-abusing women who are on methadone maintenance and attending a drug dependency unit may rear and care for their children as well as parents from a similar social background who are not drug abusers. KEY WOROS: growth, development, methadone, drug abuse aternal opiate abuse can affect many aspects of a M child's life. Pre-natal exposure may influence the development of the foetus, opiate withdrawal a t birth may produce symptoms of abstinence in the neonate, and the lifestyle and social circumstances of the abuser may affect the development and behaviour of the child. There is considerable information about the effect on the neonate of exposure to opiates in utero (Zuckerman and Bresnahan, 1991) and the neonatal abstinence syndrome (van Barr, Fleury, Soepatmis Ultee and Wesselman, 1989), but less is known about the consequences of being reared by a mother who continues to abuse these drugs. Studies from the United States (Wilson, 1989) and Denmark (Olofsson, Buckley, Andersen and Friis-Hansen 1983) have shown that children of heroin abusers are increasingly likely with age to be living with a