The differential of the exponential map on a symmetric space can be expanded (abusing some notation) as $d{\rm Exp}_X=\sum_{n=0}^{\infty}\frac{({\rm ad}X)^{2n}}{(2n+1)!}.$ This is an old (1958) result of Helgason. *Question* (EDITED): Is there any generalization to reductive homogeneous spaces?