Clinicians and researchers have long envisioned the day when computers could assist with difficult decisions in complex clinical situations. The first article on this subject appeared in the scientific literature about 60 years ago,1 and the notion of computer-based clinical decision support has subsequently been a dominant topic for informatics research. Two recent Viewpoints in JAMA highlighted the promise of deep learning in medicine.2,3 Such new data analytic methods have much to offer in interpreting large and complex data sets. This Viewpoint is focused on the subset of decision support systems that are designed to be used interactively by clinicians as they seek to reach decisions, regardless of the underlying analytic methodology that they incorporate.