The objective of this paper is to examine the long-run determinants of internal migrations from southern Italy. In order to accomplish this task, the paper develops a bootstrap test for panel cointegration analysis with dependent units. Monte Carlo simulations show that the test, based on the Continuous-Path Block bootstrap, has good power and size properties and is robust to both short- and long-run dependence across units. The empirical analysis points to income in the sending region as a key factor of the decline of migrations, with unemployment and income differentials playing only a minor role.