Came of a family prominent in business, philanthropy, and society. He was born in New York on September 23rd, 1852, and was educated in New York, the Andover Academy, and Yale, where he graduated in Arts. He gained his medical education at the College of Physicians and Surgeons attached to Columbia University. Between 1878 and 1880 he studied at Vienna, Leipzig, and Wurzburg, then set up in New York as a surgeon and attended the Charity, Bellevue, Presbyterian, Roosevelt, and Emigrant Hospitals. At the same time he held classes in surgery which were largely attended. On the opening of Johns Hopkins Hospital, Baltimore, in 1889, followed by the opening of the Medical School in 1893, he was placed in charge of the Department of Surgery, his colleagues in other departments being Osler, Howard Kelly, and Welch. The hospital gained the highest reputation. Halsted, although much hampered by ill health, surrounded himself with pupils engaged in clinical observation and research, who became distinguished surgeons and teachers of surgery - Crile, Harvey Cushing, Finney, Bloodgood, and others. Halsted gave special attention to the surgery of hernia, of cancer of the breast, and of the thyroid and parathyroid glands. The modern operation for cancer of the breast was instituted by Mitchell Banks (qv), of Liverpool, as published in 1877, 1882, and 1887, who advocated, amongst other things, a circular incision, undercutting of the skin, the removal of the pectoral fascia and lower part of the pectoralis major, as well as the axillary glands whether enlarged or not. In his Lettsomian Lectures in 1900 he stated that of 213 cases 67 were alive three to twenty years after operation, and that among the last 60 cases there had been no deaths. Halsted in 1889 proposed in addition the complete removal of the pectoralis major in every case, and that the supraclavicular glands should be excised after dividing the clavicle, though he subsequently gave up this step of the operation. In 1918 Halsted had operated 204 times: 13 patients had been lost sight of; of the 191, 39 (20 per cent) were alive and well five years after the operation, 10 had died within five years from other causes, 10 had died of metastases over five years after the excision - the greatest degree of success reached before the rise of radiotherapy. After the introduction of Lister's antiseptic methods the radical treatment of hernia concentrated on getting rid of the sac; Macewen infolded it, Arthur Barker removed it by ligaturing the neck. Attention was next directed to restoring the internal wall by replacing the transversalis fascia. Bassini sutured the internal oblique and transversalis muscles behind the spermatic cord from 1884-1888. Halsted in 1890 went further and sutured also the external oblique aponeurosis behind the cord. But O'Connor said in 1898 that atrophy of the testis might follow, and hydrocele often supervened. Halsted was the first who designed, caused to be manufactured, and adopted the rubber gloves which have come into universal use. Mikulicz and others in Germany had tried cotton gloves, which could be washed and sterilized, but which were porous. He died in September, 1922, at Entaw Place, Baltimore. His portrait is in the College Collection. In 1907 J S Sargent, RA, painted the important group of four friends - Osler, Welch, Kelly, and Halsted - which was presented to Johns Hopkins Hospital. Subject to an annual payment to his widow he left the residue of his property to the Johns Hopkins University, preferably for research in surgery. Besides the improvements already mentioned, Halsted ligatured the first part of the left subclavian artery in 1892 and in 1918 - both cases successfully. This difficult operation had been carried out previously with success by Charles Stonham in 1889, and the patient was exhibited twenty-two years later (*Proc. Roy. Soc. Med*. (Clin. Sect.), 1921, Jan. 14, xiv, 38).