Michael Forrest (1936-), physicist, spent his career in fusion research at the Atomic Energy Research Establishments at Harwell and Culham. His initial post as a scientific assistant was as an experimental spectroscopist on the ZETA experimental fusion device at Harwell. At Culham he developed laser scattering instrumentation that could accurately measure the very high temperatures of fusion plasma, frequently millionsof degrees. This expertise secured him a place in a British team invited to the Soviet Union to validate claims of exceptional results from the experimental T3 Tokamak fusion reactor. This visit validated the Tokamak concept, paving the way for the construction of similar machines, such as the Joint European Torus, JET, on which he also worked at Culham. After retirement he continued to serve as a consultant in fusion research.