Liraglutide (Victoza®) is a subcutaneously administered glucagon-like peptide-1 (GLP-1) receptor agonist produced by recombinant DNA technology and used as an adjunct to diet and exercise in the treatment of adults with type 2 diabetes mellitus. This article reviews the clinical efficacy and tolerability of liraglutide in adults with type 2 diabetes, and provides a summary of its pharmacological properties. Recently published pharmacoeconomic studies of liraglutide are also reviewed. Administered subcutaneously, liraglutide (usually 1.2 or 1.8 mg once daily) generally produced greater improvements in glycaemic control than active comparators or placebo when administered as monotherapy or in combination with one or two oral antidiabetic drugs (OADs) to adults with type 2 diabetes in numerous randomized, controlled phase III trials. These included six trials in the LEAD trial programme that was designed to evaluate the efficacy and safety of liraglutide across a continuum of antihyperglycaemic management for patients with type 2 diabetes. Liraglutide was generally well tolerated, with a low risk of hypoglycaemia evident, in the phase III trials. The most common adverse events were gastrointestinal and included nausea and diarrhoea; most events were mild to moderate in severity and decreased in incidence over time. In conclusion, liraglutide has an important place in the management of adults with type 2 diabetes across a continuum of care. As well as providing effective glycaemic control, liraglutide improves pancreatic β-cell function and leads to bodyweight loss, thereby addressing some of the unmet needs of patients treated with traditional OADs.