During a six-year (1978-1984) sediment trap study in the northwestern Mediterranean off the coast of Monaco, large variations in mass flux and carbon flux through 100 and 150 m were observed with maximum flux values occurring in late winter or early spring and minimum flux in late summer. Total particulate carbon flux was linearly related to mass flux. During March through October total particulate carbon flux represented, on average, approximately 7 % of the mass flux, whereas from November through February it averaged about 4.7 %. From recent organic carbon content data collected in the same region, it was estimated that approximately 5 % of the total mass flux through 100 and 150 m in calm seas was organic carbon (calm seas were prevalent during March through October). Organic carbon export out of the euphotic zone ("new production") ranged from 17 to 42 % of primary production. Zooplankton fecal pellets were always an abundant component of the sinking particles and the pellet carbon flux was linearly related to the total carbon flux at the three depths (50, 150 and 250 m) examined. Higher pellet fluxes were always observed at the greater depths. Pellet carbon fluxes were calculated to be roughly 25, 29 and 33 % of total particulate carbon fluxes through 50, 150 and 250 m, respectively. These estimates suggested that zooplankton fecal pellet deposition is a significant contributor to the downward particulate carbon flux in this region of the northwestern Mediterranean Sea.