Although there is a substantial role for social theory in explaining patients’ health behaviors, it does not appear that pharmacists commonly use such theories to provide patient care. This paper attempts to demonstrate an explicit link between social theory and pharmacy practice. The theory of structure and agency and the practice problem of poor medication adherence (MA) in patients with HIV/AIDS are used as exemplars to illustrate such a link. Factors influencing MA were identified from qualitative studies of adherence in patients with HIV/AIDS. All factors identified were stratified into one of four categories: agency related factors that facilitate MA; agency related factors that are barriers to MA; structural factors that facilitate MA; structural factors that are barriers to MA. Stratifying MA in this manner allows pharmacists to identify clinical interventions that are targeted towards the specific cause of MA problems.