Abstract: We describe how to exted the techniques of Goresky, Kottwitz and MacPherson to the (possibly infinite dimensional) setting of equivariant CW complexes with only even dimensional cells. We show how to compute equivariant cohomology of these spaces in a purely combinatorial way. These results give insight to many (symplectic!) examples, including certain coadjoint orbits of the loop group $LG$. This is joint work with M.\ Harada and A.\ Henriques.