The solute distribution in stir-cast Al-6 wt % Cu alloy is more uniform than that in the conventionally cast (unstirred) alloy, solidified at the same cooling rate. The Bower-Brody-Flemings model of microsegregation was modified to take account of convective interdendritic (or intercellular) solute transport in the liquid. It was found that the modified model allows a reasonable description of the observed solute distribution in both the stirred and the unstirred alloy. Differences are described in terms of two parameters: the dendrite tip undercooling constanta and the effective equipartition ratiokc, which includes the influence of convective solute transport. It is concluded that the solute distribution is more uniform the greater either of these constants becomes.