This book examines whether reintroducing copyright formalities is legally feasible. Based on a comprehensive and thorough analysis of copyright formalities, it sets out to establish the extent to which the current copyright system allows for their reintroduction. To this end, the author describes the role and functions of formalities, revisits the history of formalities at the national and international levels, examines the scope of the international prohibition on formalities, and scrutinizes the rationales behind this prohibition, including an in-depth examination of the validity of the argument that copyright is a 'natural right' and therefore should be protected independently of formalities. The author skilfully evaluates and contrasts the conflicting theories according to which formalities, on the one hand, add legal certainty to claims on the ownership of property, and, on the other, hamper individual authors from seeking adequate protection for their works. This book makes an important contribution to legal science by answering questions that so far have been neglected or only marginally addressed. To the degree that current copyright law permits reintroducing formalities, the author posits the specifications that will determine to a great extent what role and functions they may eventually fulfil: depending on the aims to be achieved, lawmakers must choose which types of formalities shall be imposed, and what their legal consequences shall be. This book goes a long way towards reinforcing the foundation for those decisions.