Among the great British clinician scientists of the 20th century, Stanley Peart was a giant. His international fame was based on a remarkable scientific contribution for research on the autonomic nervous system and the renin-angiotensin system—2 systems that play a vital role in the regulation of the circulation and the kidney. He was responsible for demonstrating that noradrenaline was the sympathetic neurotransmitter—the nature of which had eluded scientists for >3 decades and, subsequently, the nature of angiotensin, the key effector peptide hormone of the renin-angiotensin aldosterone system, and its isolation, purification, and sequencing—an outstanding achievement given the limitations imposed by the technologies of the time.