Many patients with diabetes fail to achieve their glycaemic targets despite clear evidence that glycaemic control can prevent or delay the development of costly complications in diabetes. This article describes how insulin analogues (insulins lispro, aspart, glulisine, glargine and detemir) may have a role to play in overcoming barriers to insulin acceptance and improving adherence with therapy, and examines their cost-effectiveness as determined in published studies. Cost-effectiveness studies attempt to assess all the costs and all the benefits of a particular therapy. Pharmacoeconomic models, which calculate the long-term effect of interventions, show that over periods such as 10 or 35 years the higher prescription costs of analogues are offset by a lower incidence of acute hypoglycaemic events and costly, chronic complications such as nephropathy. This results in costs per 'quality-adjusted life year' that fall well within accepted limits for good value for money. Retrospective analyses of managed care databases show that higher prescription costs for analogues are offset by lower hypoglycaemia-related costs and/or inpatient claims. Relative to human insulins, analogues provide a better balance between glycaemic control and tolerability. Patients' fear of hypoglycaemia is allayed; the pen devices used with analogues facilitate insulin injection; and the pharmacokinetic characteristics lead to increased flexibility and convenience. All these factors can help increase adherence with therapy, which may in itself be cost-saving. Taken overall, these results indicate that insulin analogues are a cost-effective therapy.