Weanling mice of the alcohol-avoiding DBA strain cross-fostered to mothers of the alcohol-selecting C57Bl strain drank twice as much alcohol as did nonfostered DBA mice. In contrast, C57Bl mice cross-fostered to DBA mothers drank the same amount of alcohol as did nonfostered C57Bl mice. Differences in maternal behavior seem to be responsible for differences in alcohol selection by weanlings.