Not monitoring adherence to oral anticancer therapies (OAT) can lead to poor clinical outcomes, including premature death as reported by Foulon et al. (Acta Clin Belg 66(2):85–96, 2011) and Greer et al. (Oncologist 21(3):354–76, 2016). Barriers to the implementation of supportive cancer care interventions in medication adherence occur with multiple hospital sites, cancer diagnoses, and numerous healthcare professionals. This commentary describes challenges and strategies from two OAT adherence trials in Australia and Switzerland to assist researchers in the design and implementation of future interprofessional trials.