<p>The goal of planetary protection is to control, to the degree possible, the biological cross-contamination of planetary bodies. Guidelines developed by the Committee on Space Research (COSPAR) are used by all spacefaring nations to guide their preparations for encounters with solar system bodies. NASA's Science Mission Directorate has convened the Planetary Protection Independent Review Board (PPIRB) to consider updating the COSPAR guidelines given the growing interest from commercial and private groups in exploration and utilization of Mars and other bodies in space.</p> <p>At the request of NASA, this publication reviews the findings of the PPIRB and comments on their consistency with the recommendations of the recent National Academies report <i>Review and Assessment of the Planetary Protection Policy Development Processes</i>.</p>