This book presents the proceedings of the 21st NextMed/MMVR conference, held in Manhattan Beach, California, in February 2014. These papers describe recent developments in medical simulation, modeling, visualization, imaging, haptics, robotics, sensors, interfaces, and other IT-enabled technologies that benefit healthcare. The wide range of applications includes simulation for medical education and surgical training, information-guided therapies, mental and physical rehabilitation tools, and intelligence networks. Since 1992, Nextmed/MMVR has engaged the problem-solving abilities of scientists, engineers, clinicians, educators, the military, students, and healthcare futurists. Its multidisciplinary participation offers a fresh perspective on how to make patient care and medical education more precise and effective.