Papua New Guinea is one of the few post-colonial states that has managed to maintain an unbroken record of democratic government, yet it is generally portrayed as a country marked by political instability with a state on the verge of collapse. In seeking to explain this apparent contradiction it is argued that extreme diversity has dissipated the force of ethnic cleavages and the fluidity of party politics has mitigated the development of a confrontational style of politics; nevertheless, the emerging pattern of ‘disorderly democracy’ has tended to undermine state capacity, posing threats to the survival of the country’s democratic system.