Political theory conventionally distinguishes between three sequential steps in the process of public appointment. One is the identification of those members of the polity who possess prior rights to submit their candidacy for a particular position; a second is the determination of the mechanisms whereby individual credentials are verified and assessed; the third is the delineation of the procedures whereby designated incumbents are formally installed into office.

Organised communities, whatever the nature of their regime, tend to make specific – often pedantic – provisions for rites of passage through all three stages. In part, the reasons are instrumental. Regularised patterns for the acquisition and transmission of authority constitute society's most convenient medium for the maintenance of political continuity and constitutional stability. Man's natural tendency towards competitiveness, runs the argument, is in the realm of public affairs best restrained by the knowledge that executive power, once conferred and confirmed in accordance with accepted conventions, cannot thereafter be lightly challenged. Fixed succession procedures thus function as constitutional safeguards; they reduce – even if they cannot entirely eliminate – the likelihood of unruly competition for place and position at the apex of government.

Equally important, although perhaps less immediately obtrusive, is a second facet of accession and succession procedures. Their existence and constant re-enactment help to perpetuate the institutional identities of the individual agencies to which they relate.