Excitation energy transfer between acriflavine and erythrosin B dyes in solutions of two different viscosities has been studied. For low acceptor concentrations decay is exponential whereas for high acceptor concentrations it fits with Förster function for energy transfer. The observed diffusion coefficients are higher than even the sum of diffusion cofficient for translational diffusion and energy migration for immobile donors. This has been attributed to the increased donor–donor transport in the presence of translational diffusion. It is interesting to note that our experimental results are in complete agreement with the theoretical results of one of the recent general models for energy transfer and migration (S. Jang et al., J. Chem. Phys. 102 (1995) 815).