While there is considerable enthusiasm for the translational and clinical applications of chronobiology, their actual implementation is not progressing as rapidly as might be expected. Here we discuss the possibility that this may relate to a combination of conceptual, methodological, evidentiary and training challenges. These are compounded by the remaining, profound cultural differences between basic and applied chronobiologists. We argue that all these issues can be overcome by cross-faculty teaching, time, patience and goodwill, together with a set of more formal actions, such as the establishment of a collaborative framework for evidence generation, the engagement of relevant stakeholders and public health campaigns based on already available evidence. We hope that chronobiology, and in particular the transformative power of circadian medicine, will change health outcomes, increase safety and improve quality of life for patients worldwide. Now is the time to bring "internal time" into medicine.