The purpose of this study is to explain how work-family conflict is related to contextual performance, specifically to organizational citizenship behavior. The hypotheses are: a) work overload and family responsibilities are positively related to work-family conflict, b) agreeableness, conscientiousness, and neuroticism moderate the aforementioned relationship, c) work-family conflict is positively related to stress in a relationship moderated by neuroticism, and d) stress mediates the negative relationship between work-family conflict and organizational citizenship behavior. Through a field study in two organizations that specialize in providing employees primary necessities, such as health, housing, and education, I found that some of the study's hypotheses were supported. Theoretical and practical implications are discussed, as well as need for further research in Colombia and elsewhere on the mechanisms through which on the one hand, employees make the decision either to exert or to withhold organizational citizenship behaviors, and on the other hand, work-family conflict leads to stress.