Sir Bernard Katz established the cellular basis of synaptic transmission at the neuromuscular junction, the contact point between nerve and muscle. With his death, we lost one of the most distinguished biophysicists of our time. He laid the foundations for our understanding of almost every aspect of synaptic transmission. Bernard Katz revealed the existence of key molecules and formally described their interaction. With the benefit of his almost magical intuition, he formulated hypotheses that are now recognized as facts.