The circular economy has gone mainstream as a goal in the transitions toward a more sustainable society. Often, however, laws that promote a circular economy remain vague or narrowly focused on resource efficiency, obscuring the fact that they have multiple environmental effects and can lead to environmental trade offs. This Article examines how to properly frame circular economy laws for sustainability, focusing on product-service systems generally and the case of car sharing in particular. Its analysis shows that a circular economy is not to be framed as an end, but as a means of striving for environmental sustainability.