(a) Legitimacy is a political concept which has to do with the citizens' approval, acceptance and recognition of the rights of their political leaders to govern. A government is considered legitimate if it comes to power not through coup or appointments, but through constitutional means. Therefore, elected governments are legitimate. However, it is argued in some quarters that the military in government may attain legitimacy if popular policies are made by it.
(b) Factors that can sustain Legitimacy are:
(i) Good Stable government: If the government policies are good, the people will continue to have trust and confidence in such governments, for example in the areas of providing social amenities and infrastructure, maintenance of law and order, obeying the provisions of the constitution, etc.
(ii) Reliable leadership: Legitimacy may be ascribed to a leader that performs creditably in office.
(iii) Periodic elections: Free and fair elections produce legitimacy. Periodic elections will help to keep it alive.
(iv) Broad based political participation: If political appointments cut across sections of the society, this can strengthen legitimacy in such systems.
(v) Regard for customs and traditions: If the government regards customs and traditions of the people, legitimacy could be sustained, for e.g. heredity is maintained in Benin Monarch, British Monarch , etc.
(vi) Ideology : If the ruling government upholds the principle of the state ideology, this can help to sustain legitimacy, e.g Capitalism in U.S.A.