Covers a longer span of time than other books - three decades enabling systematic examination of the policies of four governments: Conservative, New Labour, Coalition and Conservative.

It both provides a detailed historic account of the twists and turns of policy and legislation over the 30 year period and combines this with commentary from those intimately involved in decision making and implementation of policy and legislation.

There is a range of interviewees, including many from non-political sources.

Its unique contribution is the combination of the analysis of legislative and organisational changes with the interviewing of virtually all the most important players in the process – all surviving Home Secretaries and Ministers of Justice since 1990, junior ministers; all Directors of Prisons NOMS/HMPPS and the new National Probation Service; four Chief Inspectors of Prisons and three Chief Inspectors of Probation; the four most recently retired Lord Chief Justices.

A unique added value is the interviews with virtually all the politicians and other key players who have been involved over the past 30 years, which provide a unique commentary and insight into how they thought and how they approached their responsibilities.

The period of time in question has seen many changes in prison and probation and a detailed analysis of this in one place would be useful but, crucially, to also have the interviews of so many people makes this unprecedented.

The authors are highly respected and Professor Roy King has been a leading authority on prisons for several decades.