An empirical-analytic study was carried out using a quasi-experimental design with the aim of testing and assessing the impact of a brief intervention motivational program for the control of alcohol consumption in problem drinkers. The independent variable in this study was the intervention program, as structured upon the principles of motivational interviewing and cognitive self-control. Indicators of consumption (intensity, frequency, and risk) were the dependent variable, as were the motivational stage towards change, the state of change processes, and the expectations on consumption. Measurement of all variables was carried out with the use of previously validated instruments in three moments: a) pre-intervention; b) end of intervention and; c) fi ve weeks after treatment. 180 college students, previously detected as heavy drinkers were randomly assigned to one of three groups: (a) Individual motivational interviewing, (b) Group motivational interviewing, and (c) no intervention. Both of the motivational interventions (individual and group) led to a signifi cant decrease in indicators of consumption and to an improvement in the use of those change processes responsible for it. Nevertheless, group intervention led to a more signifi cant