OBJECTIVE: Lateral epicondylitis is a common complaint, with an annual incidence between 1% and 3% in the general population. The Dutch College of General Practitioners in The Netherlands has issued guidelines that recommend a wait-and-see policy. However, these guidelines are not evidence based. DESIGN AND SETTING: This paper presents the results of an economic evaluation in conjunction with a randomised controlled trial to evaluate the effects of three interventions in primary care for patients with lateral epicondylitis. PATIENTS AND INTERVENTIONS: Patients with pain at the lateral side of the elbow were randomised to one of three interventions: a wait-and-see policy, corticosteroid injections or physiotherapy. MAIN OUTCOME MEASURES AND RESULTS: Clinical outcomes included general improvement, pain during the day, elbow disability and QOL. The economic evaluation was conducted from a societal perspective. Direct and indirect costs (in 1999 values) were measured by means of cost diaries over a period of 12 months. Differences in mean costs between groups were evaluated by applying non-parametric bootstrap techniques. The mean total costs per patient for corticosteroid injections were euro430, compared with euro631 for the wait-and-see policy and euro921 for physiotherapy. After 12 months, the success rate in the physiotherapy group (91%) was significantly higher than in the injection group (69%), but only slightly higher than in the wait-and-see group (83%). The differences in costs and effects showed no dominance for any of the three groups. The incremental cost-utility ratios were (approximately): euro7000 per utility gain for the wait-and-see policy versus corticosteroid injections; euro12000 per utility gain for physiotherapy versus corticosteroid injections, and euro34500 for physiotherapy versus the wait-and-see policy. CONCLUSIONS: The results of this economic evaluation provided no reason to update or amend the Dutch guidelines for GPs, which recommend a wait-and-see policy for patients with lateral ...