Despite decades of research, the impact of internationalization level on performance still lacks consensus. Our objective is to show that this is partly due to the use of different methods of measuring variables. We conducted a first study on the global automotive sector over a 10-year period using various methods to measure internationalization on one hand, and performance on the other hand. Our results validate our hypotheses. We believe that by using different indicators, researchers measure very different dimensions of internationalization and performance. Our research indicates that it would be useful to return to more in-depth analyses of the link between different forms of internationalization and different facets of performance.