This study sought to examine: (a) the relative effects of baseline demographic and psychosocial factors and an intensive nutritional intervention on changes in fruit and vegetable consumption in low-income, ethnically diverse women served by the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) program in Maryland; (b) whether this intervention, designed to modify psychosocial factors associated with fruit and vegetable consumption, was successful in changing these factors; and (c) whether changes in these factors were associated with increased consumption. The same women from 15 WIC program sites were surveyed at baseline and postintervention 8 months later. Women randomized to the intervention group showed significantly greater mean change in self-efficacy, attitudes, social support, and knowledge of national consumption recommendations than control group women. Changes in all psychosocial factors were significantly associated with nutrition session attendance and increased consumption. In a hierarchical model, changes in these factors accounted for most of the intervention effect on increased consumption.