Answer
Innovative financial instruments were a key contribution of Ivar Kreuger to the financial markets. He introduced novel concepts such as the "Kreuger bond," a type of international bond that was widely used in the 1920s. These instruments facilitated cross-border capital flows and played a significant role in the development of global finance. Kreuger's financial innovations helped to connect investors and borrowers across different countries, fostering economic growth and international cooperation.