 This broader theory is, however, more developed for the relatively easy case when coalition gains are like money prizes which can be allocated arbitrarily among coalition members (the “transferable utility case”). In this case, for the two-party bargaining problem the Nash and Kalai-Smorodinsky solutions coincide and give equal gains to the two parties. The Shapley value is a solution which generalizes this to any number of parties and gives a party the average value of the marginal contribution that this party brings to all coalitions which it can join. In other words, it rewards the parties in proportion to the increase in coalition gain that they bring about by gathering with others.