Orthodontics has a commitment to precision and accuracy similar in concept to physical engineering. Both work in a 3-dimensional (3D) world-the engineer designing and modeling physical products, and the orthodontist diagnosing and treating patients. To achieve the best possible results, both fields have readily adopted and successfully implemented highly advanced mathematical techniques and sophisticated protocols. Today, a notable difference between the 2 fields relates to the data input and analysis/modeling tools that are now available. Technology advances in the past 5 years have started to erode these barriers to safely make human 3D data input as precise and easy to obtain as physical 3D object input. Many are familiar with the advances in 3D computed tomography, specifically cone-beam technology; this article focuses on a sister imaging technology called 3D surface imaging. These 3D systems enable extraoral imaging protocols to be equally precise in providing highly accurate 3D facial surface images for diagnosis, analysis, treatment monitoring, simulation, and outcome evaluation. © 2008 American Association of Orthodontists.