Equilibrium uptake data for cross-linked polyisoprene networks exposed to benzene-cyclohexane mixtures are presented : the data show that the equilibrium swelling ratio is increased by the presence of the second solvent and display virtually no evidence of selective uptake from the mixture. Bath features agree qualitatively with a Flory-Rehner description of swelling generalized to a binary mixture. Pulsed-field-gradient spin-echo NMR results for the self-diffusion coefficients of benzene and cyclohexane within the swollen networks are also obtained : they indicate that the self-diffusion coefficient of cyclohexane is significantly enhanced by the presence of benzene. These results are correlated with the results of simple sorption (weight uptake) experiments for cross-linked polyisoprene spheres exposed to the same solvents. In particular, the mutual diffusion coefficients that can be extracted from the sorption data reflect the trends found in the self-diffusion coefficients results.