A coalition is a pact or treaty among individuals or groups, during which they cooperate in joint action, each in their own self-interest, joining forces together for a common cause. This alliance may be temporary or a matter of convenience. A coalition thus differs from a more formal covenant. Possibly described as a joining of 'factions', usually those with overlapping interests rather than opposing.
Motivation of humans beings for forming coalitions can be explained in terms of evolutionary biology and evolutionary psychology. Humans have adapted to the surrounding environments over generations through the process called, "natural selection." Humans have learned and evolved into ways to endure and survive in a variety of competitions and social problems over time. In that sense, empirically, ancestral groups who socialized survived better over generations, which led to evolution of human brain to tend to form a group of a number of people, which eventually led to coalitions.
According to A Guide for Political Parties published by National Democratic Institute and The Oslo Center for Peace and Human rights, there are five steps of coalition-building:
- Developing a Party Strategy: The first step in coalition-building involves developing a party strategy that will lay the ground for successful negotiation. The more effort parties place on this step, the more likely they are to identify strategic partners, negotiate a good deal and avoid some of the common pitfalls associated with coalition-building.
- Negotiating a Coalition: Based on the strategy that each party has prepared, in Step 2 the parties come together to negotiate and hopefully reach agreement on the terms for the coalition. Depending on the context and objectives of the coalition, these negotiations may be completely secret or partially public. While some issues may be agreed on with relative ease, others may be more contentious and require different approaches to reach compromise.
- Getting Started: As negotiation begins to wrap-up, the agreement between political parties needs to be formally sealed. This includes finalizing a written agreement, securing formal approval of the deal from the relevant structures of the coalition’s member parties and announcing the coalition details to the general public.
- Working in a Coalition: As the coalition partners begin working to implement their agreement, they will need to maintain good relations by continuing efforts to increase or sustain trust and communication among the member parties. Each party will also need to strike a balance between respecting its obligations to the coalition and maintaining its individual identity.
- Drawing Lessons Learned: Regardless of whether it plans to move forward alone or in another coalition, it is important for each party to review and document lessons learned from each coalition-building experience. This will make it possible to get a clearer picture of the positive and negative impacts of coalition-building on the party, and to identify lessons learned that can inform any future coalition-building efforts.
Coalitions manifest in a variety of forms, types and terms of duration:Campaign coalitions with high intensity and long-term cooperation
Federations, characterized by relatively lower degree of involvement, intensity and participation, involving cooperation of long duration, but with members’ primary commitment remaining with their own entities
Instrumental coalitions, involving low-intensity involvement without a foundation to mediate conflict
Event-based coalitions that have a high level of involvement and the potential for future collaboration.
A coalition government, in a parliamentary system, is a government composed of a coalition of parties. In Australia, the Coalition is also used to refer to an alliance (coalition agreement) of three parties (the Liberals, Nationals and Country Liberals) existing in federal politics since 1922 - this constitutes a parliamentary coalition. A coalition of parties is also an electoral fusion. The Cambridge Dictionary defines coalition as, "the joining together of different political parties or groups for a particular purpose, usually for a limited time, or a government that is formed in this way".
Purpose. International politics dynamic is represented by coalitional competitions. In international relations, a coalition can be an ad hoc grouping of nations united for specific purposes. Although persons and groups form coalitions for many and varied reasons, the most common purpose is to combat a common threat or to take advantage of a certain opportunity resulting in the often-temporary nature of coalitions. The common threat or existence of opportunity is what gives rise to the coalition and allows it to exist. Such collaborative processes render the actors of the coalition gain political influence and potentially initiate social movements.
Characteristics. Coalition is a collaborative, both purpose-oriented and means-oriented arrangement, especially a temporary one that allows distinct people or organizational entities to pool resources and combine efforts in order to affect changes it desires. The combination of persons or entities with the same interests into one body, as a union, is variously organized and structured, but generally less formal than a covenant.
Behavior dynamics. Coalitional groups are diverse and at the same time are characterized by some degree of commonalities. Uncommonalities would lead some to perceive the group's bond as being ordinarily unlikely. However, instead of operating in historical ties, coalition members are joined by new intentions, not necessarily prior bonds. Beoyond commonalities and uncommonalities, rationality, group dynamics, and gender are also contributing factors of coalitional behaviors in international security framework. Coalition, acting as anthropomorphized entity, behaves in a way that secure its survival and confrontation to threat instinctively and the behaviors are dynamically affected by level of rationality within the entity, group dynamics, and gender perception. At the same time, coalitional entity by people is viewd as a monolith due to the tendency of cognitive simplicity, which makes it easy to overestimate its leadership. Then the coalition itself affects change in leadership that is supposed to be vice versa. Therefore, there are mutual interactions between group behavior and rationales.
Within political science, coalition theories analyze the formation, workings, power mechanism and break-up of political coalitions that are usually among states. The power of coalitions is variable, dependent on the context in which they are organizing and the strategies used by the organizers, as documented in the book Power in Coalition.
Economic agents can form coalitions. Unions can be seen as coalitions of workers (usually of the same industrial sector). The cooperation of firms on particular tasks (for example Research and Development (R&D)) has been studied by Beath et al., for example. When the agents considered are countries, the formation of an international treaty (e.g. trade agreements, or international environmental agreements) can be seen as a coalition. In economics coalition formation and stability is mostly studied with tools from game theory.
Coalitions also describe alliances between civil society organizations, such as labor unions, community organizations and religious institutions. Sometimes called labor-community coalitions, coalitions have proven to be an important strategy for social change in many contexts. Research has found that genetics and hereditary factors may play a part in how well an individual adapts to and performs within a social group coalition. Coalition of social groups might also refer to a group of citizens uniting behind a common goal. Many of these are grassroots organizations, like the Christian Coalition.
There is also activism within civil society. Activists and nonprofit groups often call themselves "coalitions" when they join together. It can be temporary or long-term. Such coalitions are defined by the cause which unites the members groups, although sometimes there is also a geographical dimension, such as in the West Suburban Faith Based Peace Coalition, based in suburban Chicago. Most often coalitions of activists and advocates support each other when one faction takes the lead in a particular movement. Coalitions of activists work best once there is a mutual respect for the strengths of each organization/individual involved, and there is less overlap.
In some instances the organization consists of only one person. The often-cited Save the Plastic Bag Coalition, for example, lists only one person, Stephen Joseph, on the contact page of its website.
A coalition is a collection of countries involved in a military operation who are unified under a single command. Examples include the Coalition of the Gulf War, assembled by President George H.W. Bush during the Persian Gulf War, as well as the "Coalition of the Willing", a phrase employed during the 2003 campaign for the war in Iraq led by the United States and its allies. A contemporary example is the United Nations coalition that intervened in the 2011 Libyan civil war against Muammar Gaddafi.
Coalitions can be studied with tools of games. The most common solution concepts for coalitional games are the Core and the notion of internal and external stability. The latter describes a situation where no coalition member wants to leave the coalition and no non-member wants to join the coalition.
In the computer field, and in the study of cognition, the entities can be called agents or daemons. By definition, agents can form coalitions.