Wellcome exists to improve health by helping great ideas thrive in four ways: funding scientists and researchers, leading in global responses to some of today’s biggest health challenges, working with policy makers to ensure that good research is well supported, and engaging the public so that people are more aware of science and health research. The Wellcome Trust (WT) provides about 60% of MLW’s funding, half of this through Core support and half from additional WT grants. WT also supports MLW scientifically by senior input and operationally.