Abstract The pituitary gland or hypophysis cerebri was first described by Galen of Pergamon in the 2nd century ad, and is considered to be the ‘master gland’ integrating hormonal signals that control numerous endocrine and metabolic functions. Since the demonstration of the hypothalamic control of pituitary function by Harris in Oxford in the 1950s, our understanding of the physiology and pathophysiology of the pituitary gland has broadened. The development of radioimmunoassays in the 1960s, the extraction of hypothalamic factors principally by Schally and Guillemin in the 1970s, the advances in immunocytochemistry, electron microscopy, and in situ hybridization methods, as well as the expansion of molecular biology have increased this understanding. Finally, the advances in modern imaging techniques and in pituitary surgery combined with the development of medical treatments for pituitary tumours have greatly expanded the therapeutic possibilities, providing successful and safe outcomes in most patients.