The paper explores organizations designed to influence a group to choose specific alternatives from a set of possible choices.  The perspective is that of an administrator that has personal objectives not shared by the group and can dictate organization but not group choice. The design works through subcommittee organization.  The variables used to manipulate the group choice are the assignment of members of the subcommittees, the assignment of alternatives for subcommittee consideration (the committee charge or jurisdiction) and the rules followed during subcommittee deliberations.  The model uses the core of game derived from social choice theory and cooperative games without side payments (in effectiveness form) as the principle that determines committee choices.  Experiments demonstrate that for a fixed profile of individual preferences the variables can be varied to structure the game such that almost any alternative is a member of the core. The resulting model is a very accurate predictor of the group choice.