Joseph Lister, 1st Baron Lister, (5 April 1827 – 10 February 1912) was a British surgeon, medical scientist, experimental pathologist and a pioneer of antiseptic surgery and preventative medicine. Joseph Lister revolutionised the craft of surgery in the same manner that John Hunter revolutionised the science of surgery.

From a technical viewpoint, Lister was not an exceptional surgeon, but his research into bacteriology and infection in wounds raised his operative technique to a new plane where his observations, deductions and practices revolutionised surgery throughout the world.

Lister's contribution to the fields of physiology, pathology and surgery were four-fold. He promoted the principle of antiseptic surgical care and wound management while working as a surgeon at the Glasgow Royal Infirmary by successfully introducing phenol (then known as carbolic acid) to sterilise surgical instruments, the patient's skin, sutures, the surgeon's hands and the ward. Secondly he researched the role of inflammation and tissue perfusion on the healing of wounds. Thirdly, he advanced diagnostic science by the microscopic analysis of specimens. Fourthly, he devised elegant strategies to increase the chances of survival after surgery. However, his most important contribution was recognising the key principle that underlay the change in surgical practice, namely converting a chance observation into a meaningful application of the scientific principles proposed by Louis Pasteur This was relating Pasteur's germ theory of fermentation to the origin of putrefaction in wounds.

Lister's work led to a reduction in post-operative infections and made surgery safer for patients, distinguishing him as the "father of modern surgery".