Board-certifying or FRCS Orth-type examination candidates do not need to have a comprehensive knowledge of spinal deformities but they are expected to be familiar with the basic principles. This review article covers definitions and terminology, curve characteristics such as methods of measurement, curve patterns, spinal balance and measures of adolescent growth. The aetiological classification is tabulated and the more important deformity types—idiopathic, congenital and neuromuscular, are described. Board-certifying or FRCS Orth-type examination candidates do not need to have a comprehensive knowledge of spinal deformities but they are expected to be familiar with the basic principles. This review article covers definitions and terminology, curve characteristics such as methods of measurement, curve patterns, spinal balance and measures of adolescent growth. The aetiological classification is tabulated and the more important deformity types—idiopathic, congenital and neuromuscular, are described.