Gas-water fluxes of CO2, O2, He, SF6, and NH3 have been calculated for conditions corresponding to the measurements of Liss et al [1981> for O2 exchange and of Smith and coworkers [Smith and Jones, 1986; Smith et al, 1991> for CO2 exchange. For each experimental run, the best value of surface temperature was selected by matching the calculated transfer velocity to the measured value for O2 or CO2, and fluxes of the other gases were than calculated for steady state, boundary layer, surface renewal, and eddy diffusion models. The results indicate that the dual tracer method should work well for sparingly soluble gases under conditions where a surface renewal model applies, and moderately well under conditions where the boundary layer model is appropriate, but they leave open the question of when such models should apply. ¿ American Geophysical Union 1995.