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"Bargaining seldom involves a single issue at a time. Politicians, diplomats and the like are forced to balance their preferences on some issues against their preferences on others, given that they probably won't get their way on all of them. A concession may be made to another party on a less important topic in exchange for that other party's support on a more vital issue. This process is known as log rolling.

The cynical trading off of one issue against another is something that politicians certainly do, but tend not to talk about. Since different groups have different priorities, log rolling will often operate to the advantage of all concerned. One kind of example involves single-issue parties and lobby groups. The groups are well placed to barter support to other parties on those matter of indifference to them."