This is a system where only one party is allowed to participate in the politics of the country. Formation of another party is not allowed. The two main types of single party systems are single party de facto and single party de jure. One party government de jure is one where a law has been passed preventing the formation of any other party for example Tanzania before 1990, Kenya after 1982 and Uganda between 1969 1971 among others. A single party government de facto is where there is no law preventing the formation of any other party but when in actual practice only one party exists. This was the case with KANU in Kenya before 1982.

Most new African states emerged into independence with relatively strong legislatures. The nature of the nationalist struggle during the colonial period had given the old Legislative Councils a central position in the political system, and a mystique had grown round the idea of parliament. Much of the rhetoric of African nationalism was saturated with liberal democratic dictatorship. Nationalist ideas were for 'One Man, One Vote', 'Undiluted Democracy', 'Majority Rule' and the like. But after independence there was a decline of the legislature in many African states. In some states parliamentary institutions did last for a while, but in general faith in parliamentary institutions soon evaporated. The song of one-partyism began to be heard in different areas, lulling many into an acceptance of its inevitability in African conditions.

Are African conditions inhospitable to competitive parliamentary institutions? Is the trend towards their elimination irreversible? In much of the discussion about this phenomenon during the 1960s the belief grew, even among liberals both within Africa and without that it had been wrong to assume that the Westminster plan could be transplanted to other areas of the globe successfully. There was also a good deal of vigorous defence of the feasibility of maintaining democratic values within a one-party system. Jomo Kenyatta, for example, issued a paper on one-party systems as they affect Africa which clearly expressed the Kenya ruling party's preference for a one-party state.

The fascinating innovation in our time is the mass party and the mass party is to be found in both one-party and two-party States. It is the nature of the organization of mass political parties. . . that is the real threat to the rule of law and democracy. Consequently, there are two-party States which are tyrannical and dictatorial and one-party States which can be said to be democratic and liberal. In other words, all two-party States are not necessarily democratic and all one-party States are not necessarily authoritarian.

In the same paper the comment was made that' "Constructive opposition from within" is... not an alien thing in so far as the traditional African society is concerned.' In other words, democracy could flourish in a single-party political system. At the same time, the divisive tendencies of a multi-party system should be avoided:
We reject a blue-print of the Western model of a two-party system of government because we do not subscribe to the notion of the government and the governed in opposition to one another. One clamouring for duties and the other crying for rights.

However, much of the optimism of the original assertions of African democratic instincts within a one-party system has evaporated. In practice it has been found that while a one-party system may succeed in eliminating ethnically based parties it may yet fail to eliminate ethnic caucuses and regional factions within the single party. The one-party umbrella may only disguise ethnic factionalism in the political process. Ethnic tensions may persist behind the facade of single-party loyalty.