This study develops a time series model of Turkish migration to Germany for the period 1963-2004 using the cointegration technique. A single cointegrating relation between the migration flow variable and the relative income ratio between Germany and Turkey, the unemployment rates in Germany and Turkey, and the trade variable, that captures intensity of bilateral economic cooperation, is found. By including the trade variable in the empirical migration function we investigate whether trade and migration are complements or substitutes: a question on which the theoretical literature does not provide a definite answer. Our results support the former view.