According to rational choice theory casework is a rational form of political participation for both voter and Member of Parliament. It increases the voter's chance to a redress of grievance and it is an important means for MPs to maximize their votes, which parliamentary activities fail to contribute to. Though rational for individual actors, casework is far from optimal for society as a whole. Disregarding isolated cases, casework does not constitute an important source of inspiration for legislative and oversight activities. A written survey among 101 Flemish MPs tends to show that a collective solution for grievances in great demand is not pursued, as casework seems electorally and personally so much more rewarding. A cure for casework cannot befound, unless it ends this structural attractiveness of constituency service. Disregarding its rationality in isolated cases, casework, because it does not result in collective measures, seems to be a meager substitute for political participation.