This unique book provides practical and legal clarity on all questions concerning landlord's consent, such as: What is a valid and effective request for consent? When can a tenant impose its desire for change on a reluctant landlord? What is a reasonable as opposed to an unreasonable refusal of consent? And what are the perils if either side calls it wrong? Since the last edition of this book in 2008, the law relating to landlord's consent, has evolved considerably. The purpose of this new edition is to bring that evolution into the much-loved analysis which have made practitioners say that previous editions have been that rare beast: a book about law that is actually enjoyable to read and which allows the practitioner and student clearly to see the wood for the trees.