The success rate of LM in non-Japanese firms is extremely low. Although many different reasons have been cited, two of them reflect a certain consensus. On the one hand, there is no agreement on which sequence to follow regarding organizational tools and cultural change during the transformation processes. On the other hand, there are also different views on what the correct rhythm should be. This article synthesizes and compares empirically the different theoretical perspectives on both issues and tests them in a wide dataset of 1,692 North American manufacturing firms. Results suggest that cultural change totally mediates the relation between the deployment of tools and enhanced plant performance. While tools play therefore an essential role as triggers for stimulating lean transformations, our evidence proves quantitatively that they will only improve performance through the cultural change they can potentially provide. These findings not only allow for the integration of Western and Japanese approaches, but also suggest a tentative sequence and rhythm in the deployment of lean tools and values.