The development of convective scaling is reviewed, along with results from its application to turbulence and diffusion data. Further analyses of a wide variety of diffusion data for (sigma sub y) and crosswind-integrated concentration are presented in nondimensional form with convective scaling, with remarkably consistent results. Preliminary data from the CONDORS convective diffusion experiment, performed at the Boulder Atmospheric Observatory in Colorado in 1982 and 1983, are included. For elevated sources, an enhancement of peak surface concentrations over those predicted by conventional Gaussian modeling is found; the effect increases as the ratio of source height to mixing depth increases. Later sections of this paper assess the effects of surface inhomogeneities on diffusion in convective conditions. Finally, examples of heat flux inhomogeneities causing stationary convective features to develop are presented.