The Nomos Commentary on Obligations Law leaves no legal question unanswered - it is up-to-date with reforms in construction contract law, travel law, numerous rental law reforms, changes brought about by the WEMoG, and many considerations of the consequences of the Corona pandemic. This extensive compendium aids in contract drafting and litigation. Fully developed for practical requirements, the commentaries provide exactly what practitioners, especially lawyers, need in obligations law: explanations with clear statements on contentious issues for direct application in cases - at the highest level, scientifically profound, and always comprehensible. Instantly accessible references to the burden of proof and presentation, cross-references to other provisions, the waivability of the provision, costs, and fees. Careful selection of cited literature and the most current case law references. The editors and authors are outstanding experts in the field and recognized specialists in their respective commentaries. For scientific depth and balance, Prof. Dr. Barbara Dauner-Lieb from the University of Cologne, Director of the Institute for Labor and Economic Law, vouches. For excellent practical applicability, Prof. Dr. Werner Langen, lawyer and specialist lawyer for construction and architectural law in Mönchengladbach, is responsible.