Tendinopathies of the elbow and in particular of the common extensor origin are a common cause of elbow pain. Part one of this two part review of tendinopathies of the elbow will focus on the pathophysiology and management of lateral elbow tendinopathy, frequently referred to as tennis elbow. Lateral elbow tendinopathy is a common condition with an incidence of 1 – 2%. The pathology arises from the origin of extensor carpi radialis brevis where changes, consistent with all tendinopathies, of angiofibroblastic hyperplasia occur secondary to repetitive micro trauma. It is not an inflammatory condition. Clinical history and examination is usually sufficient for diagnosis although MRI and ultrasound can be used. The many treatment options that have been proposed have a mixed quality of supporting evidence. Thus management protocols are difficult to define. Treatment depends on the length of symptoms. Acute presentation is managed through conservative measures including activity modification, topical NSAIDs and physiotherapy. For patients with recalcitrant symptoms, injection therapy with, for example, platelet rich plasma can be used. Alternatively surgical excision of the diseased tissue can be performed. This review article will consider the available evidence in order to identify both treatments that are effective and those that are not.