During the next decades the populations of most developed countries will grow older as a result of the low level of birth rates since the 1970s and/or the continuously increasing life expectancy. We show within a Generational Accounting framework how unsustainable the public finances of France, Germany, Switzerland and the U.S. are, given their demographic developments. Thereby our focus lies on social health insurance systems that are in addition affected by medical-technical progress. Due to the cost-increasing effect of medical-technical progress one can justifiably say that social health insurance schemes are the major drivers behind unsustainable fiscal policies.