Accurate numerical values are provided for the solution of the diffusion model of miscible fluid displacement in beds of finite length. The calculations presented here apply to the case in which a solute, uniformly distributed throughout the medium at the outset of the experiment is displaced by a solvent which may itself contain some of the solute. Results are given in dimensionless form for (i) the instantaneous concentration of solute leaving the bed, and (ii) the average solute concentration in the bed at any instant. Various limiting cases are discussed.