Hyperhidrosis is a debilitating pathophysiological condition characterized by excessive sweating. It is classified as primary focal or secondary. Primary focal hyperhidrosis affects symmetrical areas of the body, and tends to involve palms, soles of the feet, axillae and craniofacial regions, although other areas may be affected. Clinical evaluation of the patient with hyperhidrosis requires a careful history, including assessment of impact of the condition on the patient’s quality of life, occupation and social interactions. Physical examination and investigations should exclude underlying disease processes causing secondary hyperhidrosis. Treatment is directed towards the individual patient’s needs. Noninvasive treatments, used with varying degrees of success, include topical treatments; oral medications; and iontophoresis. For axillary hyperhidrosis, intradermal administration of botulinum toxin A has proven efficacy although treatments may need to be repeated. In severe palmar/plantar hyperhidrosis, endoscopic thoracic sympathectomy is an established and effective procedure, but surgery should be reserved for patients in whom less invasive treatments have proved ineffective. Clinicians should be aware of the specific deleterious side effects and potential complications of surgery, including compensatory hyperhidrosis, which in some patients can outweigh the potential benefits of intervention.