An extension of the pseudo grand canonical method of Mehta and Kofke to the direct simulation of two-phase coexistence is proposed. The new method samples an ensemble very closely related to the Gibbs ensemble but no longer employs particle transfer moves. Rather, the volumes of the two sub-systems are altered to mimic particle transfer. Convergence of the densities is guided by evaluation of the compressibility factor and chemical potential. The strength of the proposed method is that there is no restriction on how this is achieved. The method is illustrated by application to liquid-vapour equilibria in a cut and shifted Lennard-Jones 12,6 fluid. The liquid-vapour coexistence results compare favourably with existing Gibbs simulation results. The ensembles probed by pseudo grand canonical and pseudo Gibbs methods are discussed. Both methods might be applied most effectively to phase coexistence in dense phases or systems with internal degrees of freedom.