Two main questions are addressed in this work. First, the evolution of public debt ideas over the last six decades. We argue that public debt is an area of academic work in which new developments and controversies have been highly influenced by changes in the economic context. Second, the public debt experience of a developing economy, Colombia. We show how the access of the country to external financing has largely depended on activity in international capital markets, and how a long-term relationship between the country and her creditors has been forged through historical sequences of loans, defaults, and renegotiations. Regarding the internal public debt, we argue that it has played the role of shock absorber, and the formalization and empirical scrutiny of this idea is central to the econometric sections.