The James Watt International Medal is an award presented by the Institution of Mechanical Engineers to individuals who have made an outstanding contribution to mechanical engineering on an international scale. It was established in 1936 in honour of James Watt, the Scottish inventor credited with developing the modern steam engine, though the medal's selection criteria were not formally codified until 1951. The medal is awarded biennially and has, on three recorded occasions, been declined by its intended recipient without explanation, a circumstance the Institution acknowledges in its register but does not elaborate upon.