The construct of relative reinforcing efficacy (RRE) is central to many laboratory and theoretical models of drug abuse, but it has not been widely measured in applied clinical research contexts. The authors used a simulated alcohol purchase task to measure RRE in a sample of 267 college student drinkers. Participants reported their alcohol consumption across a range of prices, and their responses were well-described by a regression equation that has been used to construct demand curves in drug self-administration studies. Several measures of relative reinforcing efficacy were generated, including breakpoint, intensity of demand, elasticity, Pmax(price at which response output is maximized), and Omax(maximum alcohol expenditures). Demand for alcohol was inelastic across the initial range of prices but became elastic as price increased. Students who reported recent heavy drinking reported significantly greater intensity of demand, Omax, and breakpoint. These results provide initial support for the validity of the RRE indices generated with the alcohol purchase task. These results also provide empirical support for programs that attempt to reduce alcohol abuse by eliminating low-cost access to alcohol.