Excellence in any skill is acquired through practice. vCases is a virtual case workup program created and refined over 10 years.  Students learn diagnostic clinical reasoning through self-direction while working up realistic virtual patients. The supporting DxLibrary^®, a source of immediate information, helps by continually updating with each newly discovered case finding. After narrowing to the final diagnosis, an Epilogue provides personalized feedback comparing user with case author decisions. Use at home, with a friend, or in a class: anywhere with available WiFi. vCases meets student needs during all years of medical school.