Apart from complying with these values, other criteria for gaining membership to the Commonwealth are a constitutional link with an existing Commonwealth member state and the acceptance of Commonwealth procedures and conventions that have grown over the years. Reapplication for membership is required where a member state changes its constitutional character, for instance, from a monarchy to a republic.

The first of the CHOGM Declarations was made by heads of government at their meeting in Singapore in 1971. A study of the declarations over the decades illustrates the manner in which the Commonwealth tries to respond to changing demands and challenges. It is important to note that since the association has no constitution, these statements, deriving from intergovernmental consultation, are the driving force behind Commonwealth behavior and action. The Singapore Declaration of Commonwealth Principles, which in 1971 established binding principles, began with a definition of the Commonwealth itself, which summarizes its characteristics:

‘The Commonwealth of Nations is a voluntary association of independent sovereign states, each responsible for its own policies, consulting and cooperating in the common interests of their peoples and in the promotion of international understanding and world peace.’