Responding to and build on the work of Professor Michael Taggart, this book brings together essays on two contrasting issues concerning the scope and intensity of substantive grounds of review. Firstly, whether and to what extent review on substantive grounds such as unreasonableness, proportionality and substantive legitimate expectations should be expanded and intensified; and secondly, whether review on illegality grounds should ever retreat from the usual correctness standard. Fundamental rights as grounds of review raise both of these questions and a separate part is devoted to them. Taggart's support for expansion of substantive grounds of review was of a piece with his recognition of the need for judicial restraint or deference in appropriate contexts. The latter took the form both of his ultimate opposition to proportionality as a ground for review in non-rights cases, and of his support for varying intensity review under the illegality heading. Such awareness of the bigger picture and the need for balance within it is in short supply in the literature. This book is intended to continue Taggart's work in putting the pieces of the jigsaw back together.