Abstract Background Peripheral parenteral nutrition (PPN) currently accounts for almost 20 per cent of all parenteral nutrition administered in the UK. In the absence of consensus guidelines there is wide variation in practice. Heterogeneity of clinical trials has made direct comparisons difficult and meta-analysis impossible. Methods Medline, Embase and Cochrane databases were searched for all clinical trials relating to the use of PPN in adults. Relevant papers from the reference lists of these articles and from the authors' personal collections were also reviewed. Results and conclusions Effective PPN is possible in about 50 per cent of inpatients requiring parenteral nutrition. Evidence relating to optimal feed composition, choice of cannula, infusion technique and pharmacological manipulation is discussed, along with practical recommendations for the administration of PPN.