Jan Klabbers, born 13 August 1963, in Heumen, the Netherlands.Professor of International Law at the University of Helsinki. Whewell Professor of International Law-elect, Cambridge University (as of 1 October 2025). Member of the EU Panel to select panelists under bilateral trade and sustainable development agreements. Alternate Arbitrator, OSCE Court of Conciliation and Arbitration. Member, Finnish Academy of Arts and Sciences (elected 2014).Visiting Professor/Fellow (invited) at Hofstra Law School (2007); Graduate Institute for International and Development Studies (2008, 2013); Straus Institute for the Advanced Study of Law and Justice, New York University (2009-2010); Université Paris-II, Panthéon-Assas (2011); Armenian Diplomatic Academy, Yerevan (2015, 2016, 2021, 2022, 2023, 2024); New York University Law School (2015); Erasmus Law School, Rotterdam (2016-2018); Université Paris-I, Sorbonne (2017, 2022); LUISS Guido Carli (2021, 2022, 2023); La Sapienza University, Rome (2024).Stephan Hobe was born in Bremen, Germany, on 11 December 1957.He is the Director of the Institute of Air Law, Space Law and Cyber Law and Co-Director of the International Investment Law Centre Cologne. He is a member of various scientific associations, including President of the German Society of International Law, Vice-President of the German Association of International Law (the German ILA), a former member and now honorary member of the Board of Directors of the International Institute of Space Law, Chairman of the Panel of Legal Experts of the International Telecommunications Satellite Organization and Committee, and Board Member of the European Air Law Association as well as of the European Centre for Space Law. He is currently the Director of the Space Law Committee of the International Law Association and is still representing parties in litigation and active in investment arbitration.His scientific oeuvre spans more than 200 publications in public international law, European law, air law and space law, including Einführung in das Völkerrecht (most recently, 11th ed., 2020), Europarecht (11th ed., 2023) and Space Law (2nd ed., 2023). He is also the co-editor of the three-volume Cologne Commentary on Space Law and the collective work Cologne Compendium on Air Law. He edits the Zeitschrift für Luft- und Weltraumrecht / German Journal of Air and Space Law / Revue allemande de droit aérien et spatial, and has published approximately 350 articles on German public law, public international law, international investment law, air law, space law and cyber law.He teaches as a guest professor at various universities in Europe, Africa and Asia, is the co-founder of the Institute of Air and Space Law at the Gujarat National Law University, Gandhinagar, Gujarat, India, and holds honorary doctoral degrees from the Universities of Sofia, Bulgaria, and the Aviation University in Kiev, Ukraine.

• Disagreement Reduced to Writing: Rethinking the Law of TreatiesForewordChapter I. Messiness in the law of treatiesA. IntroductionB. Putting the ILC to work, againC. Some further messinessD. The coverage of the law of treatiesE. Causes of messinessF. Responses to messinessG. Three fundamental problemsH. Final remarksChapter II. Toward the archetypeA. IntroductionB. An overworked instrumentC. Treaty conflictD. The interim obligationE. Objective regimesF. Final remarksChapter III. The limited archetype of the VCLTA. IntroductionB. Toward the archetype: The first circleC. The second circleD. The third circleE. The fourth circle: Integral treatiesF. The fifth circle: The constitutionG. Circle zero: “Unilateral agreement” H. Final remarksChapter IV. The circumvention of disagreementA. IntroductionB. Escaping binding force: ReservationsC. Rewriting binding force: InterpretationD. Ending binding force: Termination and withdrawalE. Avoiding binding force: The (ostensibly) non-legally binding agreementF. Redirecting binding force: Framing and reframingG. Final remarksChapter V. Conclusions: Rethinking the Vienna Convention? A. IntroductionB. Some conclusionsC. The invisible collegeD. What then? E. Final remarksBibliographyCasesInternational tribunalsDomestic jurisdictionsPerspectives for Space Law in the Twenty-First CenturyIntroductionPart A. Development of general international lawChapter I. International law as a law of coexistenceChapter II. International law as a law of cooperationChapter III. International law in the era of globalisationPart. B. Space lawChapter IV. One century of development of space technology (1923-2024) Chapter V. Development of space law1. The five space treaties2. Resolutions of the UN General Assembly3. End of space lawmaking around 2000Chapter VI. A new space era in the twenty-first century? 1. Space transportation2. Micro-launchers3. Large constellations (infrastructures) of satellites4. Suborbital or non-orbital space activities5. Spaceports6. Space stations7. Mining on celestial bodies (space resource activities) 8. Living on celestial bodies (space settlement) Chapter VII. A new space law? 1. Legal requirements for new space activities2. Analysis of existing space legislation in light of new space activities3. Key requirements for revised or new space legislation compared to existing space lawSummary4. Can such changes be implemented? Methods of space lawmakingPart C. Changes to outer space legislation – possible solutionsChapter VIII. Charges for using outer space1. The use of outer space costs money2. Clarification of the legal status of space resource activities: A new law according to Article 11 (5) of the Moon Agreement? 3. Intermediate resultChapter IX. Space traffic management1. What is space traffic management? 2. Elements of STM3. STM and space law: Final remarksChapter X. An international fund for space debris remediationConclusion Space law in the era of globalisationBibliography

Jan Klabbers, born 13 August 1963, in Heumen, the Netherlands.Professor of International Law at the University of Helsinki. Whewell Professor of International Law-elect, Cambridge University (as of 1 October 2025). Member of the EU Panel to select panelists under bilateral trade and sustainable development agreements. Alternate Arbitrator, OSCE Court of Conciliation and Arbitration. Member, Finnish Academy of Arts and Sciences (elected 2014).Visiting Professor/Fellow (invited) at Hofstra Law School (2007); Graduate Institute for International and Development Studies (2008, 2013); Straus Institute for the Advanced Study of Law and Justice, New York University (2009-2010); Université Paris-II, Panthéon-Assas (2011); Armenian Diplomatic Academy, Yerevan (2015, 2016, 2021, 2022, 2023, 2024); New York University Law School (2015); Erasmus Law School, Rotterdam (2016-2018); Université Paris-I, Sorbonne (2017, 2022); LUISS Guido Carli (2021, 2022, 2023); La Sapienza University, Rome (2024).Stephan Hobe was born in Bremen, Germany, on 11 December 1957.He is the Director of the Institute of Air Law, Space Law and Cyber Law and Co-Director of the International Investment Law Centre Cologne. He is a member of various scientific associations, including President of the German Society of International Law, Vice-President of the German Association of International Law (the German ILA), a former member and now honorary member of the Board of Directors of the International Institute of Space Law, Chairman of the Panel of Legal Experts of the International Telecommunications Satellite Organization and Committee, and Board Member of the European Air Law Association as well as of the European Centre for Space Law. He is currently the Director of the Space Law Committee of the International Law Association and is still representing parties in litigation and active in investment arbitration.His scientific oeuvre spans more than 200 publications in public international law, European law, air law and space law, including Einführung in das Völkerrecht (most recently, 11th ed., 2020), Europarecht (11th ed., 2023) and Space Law (2nd ed., 2023). He is also the co-editor of the three-volume Cologne Commentary on Space Law and the collective work Cologne Compendium on Air Law. He edits the Zeitschrift für Luft- und Weltraumrecht / German Journal of Air and Space Law / Revue allemande de droit aérien et spatial, and has published approximately 350 articles on German public law, public international law, international investment law, air law, space law and cyber law.He teaches as a guest professor at various universities in Europe, Africa and Asia, is the co-founder of the Institute of Air and Space Law at the Gujarat National Law University, Gandhinagar, Gujarat, India, and holds honorary doctoral degrees from the Universities of Sofia, Bulgaria, and the Aviation University in Kiev, Ukraine.

• Disagreement Reduced to Writing: Rethinking the Law of TreatiesForewordChapter I. Messiness in the law of treatiesA. IntroductionB. Putting the ILC to work, againC. Some further messinessD. The coverage of the law of treatiesE. Causes of messinessF. Responses to messinessG. Three fundamental problemsH. Final remarksChapter II. Toward the archetypeA. IntroductionB. An overworked instrumentC. Treaty conflictD. The interim obligationE. Objective regimesF. Final remarksChapter III. The limited archetype of the VCLTA. IntroductionB. Toward the archetype: The first circleC. The second circleD. The third circleE. The fourth circle: Integral treatiesF. The fifth circle: The constitutionG. Circle zero: “Unilateral agreement” H. Final remarksChapter IV. The circumvention of disagreementA. IntroductionB. Escaping binding force: ReservationsC. Rewriting binding force: InterpretationD. Ending binding force: Termination and withdrawalE. Avoiding binding force: The (ostensibly) non-legally binding agreementF. Redirecting binding force: Framing and reframingG. Final remarksChapter V. Conclusions: Rethinking the Vienna Convention? A. IntroductionB. Some conclusionsC. The invisible collegeD. What then? E. Final remarksBibliographyCasesInternational tribunalsDomestic jurisdictionsPerspectives for Space Law in the Twenty-First CenturyIntroductionPart A. Development of general international lawChapter I. International law as a law of coexistenceChapter II. International law as a law of cooperationChapter III. International law in the era of globalisationPart. B. Space lawChapter IV. One century of development of space technology (1923-2024) Chapter V. Development of space law1. The five space treaties2. Resolutions of the UN General Assembly3. End of space lawmaking around 2000Chapter VI. A new space era in the twenty-first century? 1. Space transportation2. Micro-launchers3. Large constellations (infrastructures) of satellites4. Suborbital or non-orbital space activities5. Spaceports6. Space stations7. Mining on celestial bodies (space resource activities) 8. Living on celestial bodies (space settlement) Chapter VII. A new space law? 1. Legal requirements for new space activities2. Analysis of existing space legislation in light of new space activities3. Key requirements for revised or new space legislation compared to existing space lawSummary4. Can such changes be implemented? Methods of space lawmakingPart C. Changes to outer space legislation – possible solutionsChapter VIII. Charges for using outer space1. The use of outer space costs money2. Clarification of the legal status of space resource activities: A new law according to Article 11 (5) of the Moon Agreement? 3. Intermediate resultChapter IX. Space traffic management1. What is space traffic management? 2. Elements of STM3. STM and space law: Final remarksChapter X. An international fund for space debris remediationConclusion Space law in the era of globalisationBibliography