What are the dynamic consequences of comprehensive integration shocks? The answer to this question appears all but trivial. A dynamic macroeconomic model is set up of a small open economy with capital mobility, migration and increasing returns to scale. The model features multiple equilibria as well as (local and global) indeterminacy. Despite its simplicity, the model creates a rich set of plausible implications. This paper clarifies the mechanics that may lead an integrating economy to the good or to the bad equilibrium by showing how fundamentals and expectations interact in the process of equilibrium selection. The model is applied to replicate two striking empirical characteristics of macroeconomic development in East Germany since 1990.