Private autonomy is a fundamental principle of civil law, even more so against the background of increasing Europeanization. Yet, how is this principle implemented in the Proposal for a Common European Sales Law (CESL) for German and Polish law? This volume contains the informative proceedings of an international conference on "Private Autonomy in Germany, Poland, and Europe" held at the University of Leipzig. The topics range from fundamental aspects, such as the term 'autonomy' as a legal axiom, to specific issues like the freedom of contract in the CESL, and the control of unfair contract terms in business-to-business transactions.