Many theorists have debated the approaches that should be used to reduce the rates of reoffending. In recent decades, much of this has been codified into principles to guide correctional staff and organisations. However, despite these guidelines, agencies that closely follow these principles appear to be the exception rather than the rule. This book combines extensive on-the-ground experience in correctional agencies with an in-depth understanding of the What Works literature. There are many day-to-day pressures on both staff and organisations that combine to virtually ensure that many of these principles are not adhered to. So ubiquitous are these pressures that the book uses a metaphor of a helicopter: unlike an airplane, which is naturally stable in level flight, a helicopter's natural instinct is to flip upside down and crash into the ground. Similarly, the natural instincts of correctional organisations are to not comply with the principles of effective intervention. Finally, drawing upon all these failures, the book suggests realistic methods for overcoming these problems, including re-articulating the What Works principles and describing ways of operating that are both achievable and consistent with these principles.