Abstract. Let G be a complex algebraic group and L an algebraic subgroup of G. The quotient space G/L is called weakly commutative if a generic orbit of the action G : T * (G/L) is a coisotropic submanifold. We classify weakly commutative homogeneous spaces N L/L in the case where L is a reductive group and the natural representation L : n/[n, n], where n is the tangent algebra of the group N , is irreducible.