Two-level game theory
Two-level game theory is a political model, derived from game theory, that illustrates the domestic-international interactions between states. It was originally introduced in 1988 by Robert D. Putnam in his publication "Diplomacy and Domestic Politics: The Logic of Two-Level Games".
Putnam had been involved in research around the G7 summits between 1976 and 1979. However, at the fourth summit, held in Bonn in 1978, he observed a qualitative shift in how the negotiations worked. He noted that attending countries agreed to adopt policies in contrast to what they might have in the absence of their international counterparts. However, the agreement was only viable due to strong domestic influence - within each international government - in favour of implementing the agreement internationally. This culminated in international policy co-ordination as a result of the entanglement of international and domestic agendas.
The Model
The model views international negotiations between states as consisting of simultaneous negotiations at two levels.- Level 1: The international level, and
- Level 2: The intranational level.
Win-Sets
At the international level, countries will approach negotiations with a defined set of objectives. It is expected that chief negotiators of both states arrive at a range of outcomes where their objectives overlap. However, before committing to this, the chief negotiator must seek approval from domestic actors. This ratification can be in the form of both formal voting requirements or informal methods, such as public opinion polls. Due to a potential difference in domestic concerns, the full range of agreement outcomes at the international level may not necessarily be approved. As such, the possible agreement outcomes at the international level that are accepted by domestic interest groups is defined as a state's "win-set". International agreements only occur when there is an overlap between the win-sets of the states involved in the international negotiations.Win-set size plays an important role in determining the success of negotiations at the international level. Naturally, the larger the win-set, the more likely the win-sets will overlap, potentially leading to successful negotiations. Conversely, negotiations are more likely to fail when opposing state's win-sets are smaller. The perceived win-set size, however, is just as important as the actual win-set size. If a state's win-set size is perceived to be large, the opposing state will, therefore, have greater bargaining power. Alternatively, if a state's win-set is perceived to be rather small, this can lead to them attaining an advantage in negotiations, whereby they can influence the opposing state to concede more in order for negotiations to be a success.