Patient Group Directions (PGDs) have been used in clinical practice for a decade. They enable non-medical practitioners to supply medicines to patients, in certain legally defined circumstances, without a doctor's prescription and in accordance with a pre-defined protocol. The authors aimed to review the existing literature in order to identify and evaluate the evidence regarding the quality, safety and acceptability of PGDs within care systems and their impact on health outcomes. Searches of relevant databases were conducted, articles screened against eligibility criteria and relevant data extracted. A number of key issues emerged from the data including quality and safety of practice, acceptability to patients and practitioners, access to treatment and implications for professional roles and responsibilities. There were no data related to health outcomes. The review concludes that while PGDs may be an acceptable way to deliver care, their impact on patient outcomes and health status has been poorly studied.