This rich volume is an homage to the significant impact Professor Siegfried Wiessner has had on scholarship and practice in many areas of international law. It is also a collection of thought-provoking, original essays, exploring topics as diverse as theory about law, human rights, the rights of indigenous peoples, the rule of law, constitutional law, the rights of migrants, international investment law and arbitration, space law, the use of force, and many more - all integrated by the problem and policy-oriented framework of what has come to be known as the New Haven School.