Thalassemia is one of the most common genetic disorders worldwide and presents major public health and social challenges in areas of high incidence. The frequency of this disorder varies considerably with geographic locations and racial groups. Thalassemia refers to a group of inherited hemolytic anemia disorders that involve defects in the synthesis of hemoglobin α- or β-polypeptide chains. It leads to decreased hemoglobin production and hypochromic microcytic anemia associated with erythrocyte dysplasia and destruction. Homozygous β-thalassemia (also known as thalassemia major, Cooley's anemia, or Mediterranean anemia) is associated with the most severe signs and symptoms. Thalassemia major (TM) is a life-threatening condition that commonly manifests during early infancy, after which progressive pallor, severe anemia, and failure to thrive are common. Children with TM often develop feeding problems, recurrent fever, bleeding tendencies (especially epistaxis), susceptibility to infection, pathologic fractures of long bones and vertebrae, endocrine abnormalities, splenomegaly, lack of sexual maturation, and growth retardation. This book discusses cures and treatments available for thalassemia, as well as the causes and the type of long-term health outcomes it may cause.