Purpose of Review To provide an overview of a selection of largely neglected psychological risk factors for nonadherence, and to offer new approaches to improve medication adherence. Recent findings Current adherence research and intervention programs focus on a few risk factors for nonadherence, such as complexity of the drug regimen. In addition, other important risk factors of nonadherence are neglected or insufficiently addressed. There is good evidence for the significant role of the quality of the patient–healthcare provider relationship. Other risk factors like the individual history of nonadherence, the lack of acceptance of having a treatable disorder, fear of side-effects, comorbid depression, and cognitive impairment have been broadly neglected in adherence programs, although they offer a powerful key to improve adherence-oriented interventions. Summary Current research on determinants of nonadherence has focused on a few risk factors, while neglecting crucial psychological predictors of nonadherence. The personalized consideration of a multiplicity of risk factors offers a new basis for the development and evaluation of interventions to better promote adherence.