Leprosy, also called Hansen’s disease, is known since ancient times. It is a curable, slow, progressive lifelong contagious disease, caused by an intracellular, rod shaped, aerobic, slow growing bacterium, Mycobacterium leprae. Leprosy affects the skin, peripheral nerves, and mucosal portion of upper respiratory tract and may also affect other organs. Leprosy is not critically contagious. Early diagnosis and treatments prevent nerve involvement, which is considered to be the hallmark of leprosy. Its diagnosis is carried out from a number of distinct clinical presentations which should be complemented by skin bacilloscopy and histopathology. Highly effective MDT (multidrug therapy) is used as a medication which aims to eliminate the causal organism in the shortest possible time. It involves three major drugs: dapsone, rifampicin (Rifadin), and clofazimine (Lamprene). The WHO has been providing free treatment for all people suffering from leprosy since 1995. This chapter focuses on the clinical and diagnostic features of leprosy as well as the current drugs used in the treatment along with their pharmacokinetics.