The quantum commutations RT T = T T R and the orthogonal (symplectic) conditions for the inhomogeneous multiparametric q-groups of the B n , C n , D n type are found in terms of the R-matrix of B n+1 , C n+1 , D n+1 . A consistent Hopf structure on these inhomogeneous q-groups is constructed by means of a projection from B n+1 , C n+1 , D n+1 . Real forms are discussed: in particular we obtain the q-groups ISO q,r (n + 1, n − 1), including the quantum Poincaré group.