Ferguson began in 1900 to sell and repair automobiles and motorcycles, and in 1909 he designed and built his own airplane, in which he made the first recorded flight over Ireland. During World War I he supervised the operation of farm machinery in Ireland. Impressed by the need for a dependable, low-cost tractor, he perfected the Ferguson system of tractor-implement integration in the late 1930s; in this system, the linkages and controls on the hitch made the tractor and implement work as a single unit operated almost entirely from the driving seat.

In 1938 Henry Ford agreed to manufacture the Ferguson tractor in the United States. The agreement terminated after World War II, and Ferguson began to manufacture his own equipment in Great Britain and the United States.