John Lawrence Le Breton Hammond (18 July 1872 – 7 April 1949) was a British journalist and writer on social history and politics.
A number of his best-known works were jointly written with his wife, Barbara Hammond (née Bradby, 1873–1961).
She was the sister of poet and novelist G. F. Bradby.
He was educated at Bradford Grammar School and St John's College, Oxford, where he read classics.
He was editor of the Liberal weekly The Speaker from 1899 to 1906.