In mathematical representation theory, the Harish-Chandra transform is a linear map from functions on a reductive Lie group to functions on a parabolic subgroup. It was introduced by .
The Harish-Chandra transform fP of a function f on the group G is given by
fP(m)=a-\rho\intNf(nm)dn
where P = MAN is the Langlands decomposition of a parabolic subgroup.