Concentrations of surface-active organic complexes of copper in coastal seawater were used to estimate their transport from the water column to the air-sea interface by molecular diffusion and bubble scavenging. Under average wind conditions observed in Massachusetts Bay, molecular diffusion to the air-sea interface was the primary transport mechanism. Estimated diffusion flux rates ranged from 3.8 to 210¿10-17 mol Cu cm-2 s-1, with a mean value of 62¿10-17 mol Cu cm-2 s-1. Temporal variability in the flux rates was directly related to estimated rates of primary production, presumably due to the biological production of surface-active organic matter within the bulk water. Flux rates due to bubble scavenging were generally 3 orders of magnitude less than those observed for diffusion, with a mean value of 2.3¿10-19 mol cm-2 s-1 for particulate Cu and 3.7¿10-19 mol cm-2 s-1 for dissolved Cu. Temporal variability of the estimated bubble-mediated fluxes reflected sensitivity to changes in wind stress, as well as the variability in concentration of the surface-active forms of copper. Residence times of copper in the sea-surface microlayer, based on a comprehensive estimate of the flux of copper from bulk water and atmospheric sources, ranged from 2 min during a phytoplankton bloom period to 21 min during the winter months. Estimates of the flux of surface active forms of copper from the water column to the air-sea interface suggest that the entire inventory of copper within the surface mixed layer of Massachusetts Bay can be cycled through the microlayer within approximately 50 days. This is of the same timescale as the residence time of copper within the surface mixed layer of Massachusetts Bay, indicating that a major portion of copper within the surface mixed layer will be transported to the microlayer before removal from the mixed layer. The formation and transport of surface-active forms of copper may significantly influence the bio-geochemical behavior of copper and, perhaps, other metals within the surface mixed layer. ¿ American Geophysical Union 1996