This chapter adopts a more empirical and descriptive approach to the issue of imprisonment rates by comparison between international figures, before turning to imprisonment rates across the Australian jurisdictions, highlighting the wide range of variation hidden by national statistics. It then looks at how those rates are affected by the actions of parliaments and the courts and the way in which those two key players in the criminal justice landscape interact in ways that impact on the length of time served by prisoners. The chapter also looks at the effect that legislation has on the size of the prison population. It is difficult to discuss the last 40 years thematically without the need to traverse backwards and forwards across the period. There is international evidence that in recent decades increased imprisonment rates are not in line with underlying levels of recorded crime.