In 1885, Galloway proceeded to the
Straits Settlements to practise as a doctor and arrived in
Singapore on February 15. There he acquired the practice of a British doctor and soon built up a large clientele. Later, he became the medical adviser to the
Johore royal family, and in 1895 accompanied family members to London to bring back the embalmed body of the Sultan of Johore. He was decorated with the
Order of the Crown of Johore, 2nd class for service to the Sultan in 1896, which was promoted to 1st class in 1914. Galloway was an unofficial Member of Executive Council of the Straits Settlements from 1903 to 1914, and again in 1921, but resigned when he was nominated to the Executive Council, being the first unofficial to occupy such position, where he served until 1929. He was also appointed to the Johore Executive Council. He taught in the Straits Settlements and
Federated Malay States Government Medical Schools. He was Vice-Chairman of the Straits Opium Commission; President of the
Royal Asiatic Society, Straits Branch; and Fellow of the
Royal Society of Medicine. He was founder and president of Straits Medical Association, and founder of the
British Medical Association, Malaya branch. He was made Grand Prior of the
Order of the Hospital of St John in 1909. In 1924, he became the first doctor in Malaya to be knighted. He retired from practice in 1931. == Publications ==