Researchers and policy makers tend to treat monetary, financial and fiscal policies separately. In the interest of clear accountability, countries often create three distinct policy institutions, each assigned to focus on its own objective-macroeconomic stability, financial stability or government debt sustainability. This tendency stems partly from a belief that the spillovers among policies are small enough to be negligible. Real-world developments since 2007 belie that belief.
Bundesbank initiated the Trinity research network together with