Excessive sweating from the palms and soles, known as palmoplantar hyperhidrosis, affects both children and adults. Diagnosis of this potentially embarrassing and socially disabling condition is based on the patient's history and visible signs of sweating. The condition usually is idiopathic. Treatment remains a challenge: options include topical and systemic agents, iontophoresis, and botulinum toxin type A injections, with surgical sympathectomy as a last resort. None of the treatments is without limitations or associated complications. Topical aluminum chloride hexahydrate therapy and iontophoresis are simple, safe, and inexpensive therapies; however, continuous application is required because results are often short-lived, and they may be insufficient. Systemic agents such as anticholinergic drugs are tolerated poorly at the dosages required for efficacy and usually are not an option because of their associated toxicity. While botulinum toxin can be used in treatment-resistant cases, numerous painful injections are required, and effects are limited to a few months. Surgical sympathectomy should be reserved for the most severe cases and should be performed only after all other treatments have failed. Although the safety and reliability of treatments for palmoplantar hyperhidrosis have improved dramatically, side effects and compensatory sweating are still common, potentially severe problems.