Today, consent is a fundamental concept in the European legal framework on data protection. The analysis of the historical and theoretical context carried out in this book reveals that consent was not an intrinsic notion in the birth of data protection. The concept of consent was included in data protection legislation in order to enhance the role of the data subject in the data protection arena, and to allow the data subject to have more control over the collection and processing of his/her personal information. This book examines the concept of consent and its requirements in the Data Protection Directive, taking into account contemporary considerations on bioethics and medical ethics, as well as recent developments in the framework of the review of the Directive. It further studies issues of consent in electronic communications, carrying out an analysis of the consent-related provisions of the ePrivacy Directive.