The interest rate is considered the most important financial variable. Harald Stoklossa systematically develops an empirical interest rate structure theory. This allows for a comprehensive explanation of the determinants as well as a better forecast of the interest rate structure. The interest rate structure represents the inherent economic basis for the strategic planning and management of financial institutions, as well as for the valuation of financial instruments. Last but not least, the interest rate structure is also an indicator of the long-term welfare development of an economy.