Groups quasi-isometric to symmetric spaces

We determine the structure of finitely generated groups which are quasi-isometric to symmetric spaces of noncompact type, allowing Euclidean de Rham factors If $X$ is a symmetric space of noncompact type with no Euclidean de Rham factor, and $\Ga$ is a finitely generated group quasi-isometric to the product $\E^k\times X$, then there is an exact sequence $1\ra H\ra\Ga\ra L\ra 1$ where $H$ contains a finite index copy of $\Z^k$ and $L$ is a uniform lattice in the isometry group of $X$.