We study a general aggregation problem in which a society has to determine
its position on each of several issues, based on the positions of the members
of the society on those issues. There is a prescribed set of feasible
evaluations, i.e., permissible combinations of positions on the issues. Among
other things, this framework admits the modeling of preference aggregation,
judgment aggregation, classification, clustering and facility location. An
important notion in aggregation of evaluations is strategy-proofness.