A frontal filament on the shelf break in the Balearic Sea was examined using hydrographic, drifter and satellite sensor measurements. The filament was a tongue of low-salinity shelf water marked by a sharp frontal boundary. During the four-day study period, the filament moved across the shelf break with a speed of about 20 cm/s. While drifters generally followed this movement, there were large relative motions between drifters and the filament. Particle velocities in the filament generally were larger than the advancing speed of the filament. This resulted in a strong flow convergence near the head of the filament. The hydrographic data also indicated a subduction of low-salinity shelf water in the area of the front. Observations suggest that the frontal convergence may be an important process in the exchange of material across shelf/slope fronts.