Worldwide more deaths occur due to conditions that can be ameliorated by behavior change. Changing health behaviors using models popularized in non-western countries has not proven particularly successful. The purpose of this study was to test variables elicited during qualitative interviews and cultural conversations to develop a model of health behavior change from the ground up in Vietnam. Village leaders and women representatives from the Women's Committee were trained as health advocates to facilitate changes in health practices that led to parasitic and infectious diseases. The health advocates visited 156 families to assess household conditions and assist women head-of-households in applying new behaviors to water treatment, personal hygiene, proper latrining and proximity of animals to humans. Predictors that were tested were self-efficacy, social desirability, internal and external control, and outcome expectations. The correlational and regression design resulted in self-efficacy alone predicting both home hygiene and family health with a large effect size. Social desirability appears to play a different role than in western culture studies. Outcome expectations and control were not predictive. A cultural analysis of the results is included.