Trends in public attitudes toward legal abortion were analyzed for 1972 and 1978. Data were drawn from seven independent probability samples (N = 10,652) of English-speaking persons 18 years of age or older living in noninstitutional arrangements within the continental United States. Attitudes were derived from responses to six items asking whether it should be possible for a pregnant woman to obtain a legal abortion under six different conditions. Guttman Scalogram Analysis revealed two predominant patterns; approval for all six reasons and approval only for the hard reasons (safeguarding the woman's health, preventing birth of a deformed child, or treating rape). Two major shifts were noted in the level of approval; a considerable increase in 1973 for each reason and a sharp decline in 1978 for all but woman's health and rape. These shifts paralleled the introduction of laws pertaining to abortion.