The NASA Science Mission Directorate/Earth Science Division's (SMD/ESD's) Earth Venture (EV) is a program element within the Earth System Science Pathfinder Program. At the request of NASA, this report examines the Earth Venture Instrument (EV-I) and Earth Venture Mission (EV-M) elements of Earth Ventures and explores lessons learned in the more than 10 years since selection of the first EV mission, including a review of the foundational principles and approaches underlying the program.