In this paper we use results from the theory of tensor products of Banach spaces to establish the isometry of the space of (1, p)-summing sequences (also known as strongly p-summable sequences) in a Banach space X, the space of nuclear X-valued operators on rho(p) and the complete projective tensor product of V with X. Through similar techniques from the theory of tensor products, the isometry of the sequence space LP(X) (recently introduced in a paper by Bu, Quaestiones Math. (2002), to appear), the space of nuclear X-valued operators on LP(0, 1) (with a suitable equivalent norm) and the complete projective tensor product of L-p(0, 1) with X is established. Moreover, we find conditions for the space of (p, q)-summing multipliers to have the GAK-property (generalized AK-property), use multiplier sequences to characterize Banach space valued bounded linear operators on the vector sequence space of absolutely p-summable sequences in a Banach space and present short proofs for results on p-summing multipliers. (C) 2003 Elsevier Science (USA). All rights reserved.