The spatial and temporal variation in organic acids and dissolved organic carbon (DOC) in freshwater ecosystems and those mechanisms which effectively regulate this variability were the primary topics for discussion. The approach was to document what is known as a result of field observations and identify what we believe to be the most important unknowns. The context of these discussions was variability in DOC concentration and quality. Fluxes per se, although extremely important to ecosystem function, were not the central issue. We recognize that DOC is a bulk parameter for organic molecules, similar to conductivity for inorganic solutes. It yields information primarily on the most abundant organic compounds, and these are often the compounds of low biological flux within aquatic ecosystems. In this discussion, the term DOC is used as a surrogate for organic acids. It is recognized that not all DOC molecules are acidic. However, a case for using DOC as an approximate measure of the influence of organic acids can be made on several grounds. 34 refs., 3 figs.