The aim of this study was to identify barriers to medication adherence in adolescent transplant recipients. Eighty adolescent transplant recipient families reported in an open-ended manner about barriers to medication adherence. These responses were then coded to reflect potentially important themes associated with medication adherence. The themes derived included: forgot/distracted, poor planning/scheduling issues, physical barriers/medication issues, and voluntary resistance/attempts to be normal. Inter-rater reliability for barrier coding was very high (k = 0.91). Patients who were classified as non-adherent reported significantly more overall barriers, more forgot/distracted barriers, and more voluntary resistance/attempts to be normal barriers than those classified as adherent. Non-adherence was also found to be more likely when adolescents, as opposed to parents, were responsible for administering the medication. Further, non-adherence was more likely when taking morning rather than evening doses. These findings are explained with an emphasis on potential remedies that directly address the stated barriers.