Abstract: Departing from the basic optimal control setup for growing open economies in continuous time, we put forward one main hypothesis: Is the macrodynamics structure of open economies governed by endogenous growth and cycles? To tackle this hypothesis, we strip off the classical open economy problem from all institutional frameworks and evaluate our hypothesis assuming non linear convex financial adjustment in the form of risk premia on foreign holdings and investment adjustment costs on domestic capital. By imposing always dynamical rules for adjustment, we are able to obtain meaningful dynamical systems that confirm our hypothesis in a conceptual level and pave the route for the further introduction of endogenous cycles and growth dynamics in mainstream economic growth theory.