Medication therapy management (MTM) has been described as a set of procedures that include: medication review, assembly of a personal medication record, development of action plans, intervention when necessary, and follow-up. However, evidence showing the effectiveness of general MTM interventions is scant. MTM has often been performed separately from patients' usual sources of care (i.e., at pharmacies). This could limit its effectiveness since medication-related concerns would be discussed by clinicians who are not aware of the regimen intended by patients' prescribers. Cost is another barrier to widespread use of MTM.