Thalassemia is an autosomal recessive haemoglobinopathy caused by reduced or absent production of one or more globin chains (alpha or beta). While some patients remain asymptomatic, common clinical features include anaemia, jaundice, hepatosplenomegaly, failure to thrive, and recurrent infections. An essential step in diagnosis is the exclusion of iron deficiency anaemia. Confirmatory investigations typically include haemoglobin electrophoresis and genetic (DNA) testing. This chapter also outlines key evidence for the outpatient and ambulatory management and monitoring of thalassaemia.