Hanseniasis is a systemic, infectious disease whose etiologic agent (Mycobacterium leprae or Hansen’s bacillus) has a predilection and primarily affects the skin and peripheral nerves. It presents chronic evolution that can be interrupted by acute episodes known as hansenic reaction. Diagnosis is mainly clinical, based on a good anamnesis and physical examination of the skin and nerve trunks. The multidrug therapy, as it is known today, was first oriented by WHO in 1982 and it is a combination of three (rifampicin, dapsone, and clofazimine) drugs that are safe and effective in treating hanseniasis and to prevent the emergence of drug resistance. If untreated, the disease can progress to other organs and can cause nerve damage, leading to muscle weakness and atrophy, and permanent physical disabilities and deformities proper to the disease. These deformities are responsible by the stigma and prejudice against people affected by hanseniasis. Prevention of disabilities begins with diagnosing hanseniasis sufficiently early, treating with multidrug therapy, recognizing and treating reactions and neuritis. It is a compulsory reporting disease worldwide.