The Spanish Constitution gives citizens the right to work and decent housing. The millions of people who have been to stop or thousands of mortgage holders evicted by banks can legitimately ask the following question: "We have the right to work and housing, but who has the duty to provide us with it? '.

This book considers the content of rights are the duties which aims to meet the first. A law that does not correspond to any duty is absolutely empty of content right. Faced with the countless number of books aimed at analyzing the nature, rationale, or to establish a list of the rights of persons, this volume focuses on the duties corresponding to those rights. So this is not a book about rights. The book is homework.