In the summer of 2000, he helped re-plan the Program as a chain of scientifically, technologically and operationally interrelated missions with a spacecraft launched to Mars every two years. He led the Program for the next five years, a span of time that included the successful landing of the Mars Exploration Rovers, Spirit and Opportunity. All told, from 2000-2012 there has been an unprecedented 6 consecutive successful American missions to Mars (4 landers and 2 orbiters) based on the roadmap devised in the summer of 2000.