This book seeks to explore the potential and actual value of parliamentary debates as a source of legislative justification. Drawing on a sample of recent Spanish legislation, the papers collected here analyse (critically) the rationale of several laws or legislative measures as it can be reconstructed from the respective parliamentary discussions. All issues covered have given rise to intense political, legal and social controversy: they range from the combat against gender violence, the legal status of bullfighting, the protection of crime victims and the so-called ¿push-backs¿ at the border, to the regulation of euthanasia, the minimum living income, underage girls¿ access to abortion, and joint child custody. The volume is organised into two main parts. The first group of case studies adopt a legisprudential perspective and examine parliamentary deliberations in the light of the theory and methodology of legislative justification, the contributions in the second part follow approaches that fall outside ¿ but are largely compatible with ¿legisprudence, and deal with aspects such as the rhetorical strategies employed by MPs when debating bills, and the role of elected legislators as constitutional interpreters.