We develop a Fiscal Frontier which traces out the maximum government debt level that can be sustained at a given welfare cost. Through duality, the intertemporal policy mix underpinning the Frontier mirrors standard Ramsey policy and defines an upper limit on the welfare gains that can be...

This paper studies price stability and debt sustainability when the real rate exceeds trend growth (r g) in a New Keynesian model with endogenous technology growth through R&D. Under debt-stabilizing ("passive") fiscal policy the Taylor principle is not sufficient for determinacy. Instead,...