Systems and methods for selecting a mask system for a patient are provided. Certain example embodiments include generating 3D contours of patients and selecting mask systems based at least on these contours. These contours may be generated by using, for example, a cushion of translatable pins, a nasal cannular scanning device, and/or a shadow stereopsis sensor. Certain other example embodiments allow images and/or videos to be captured and optionally synchronized. Then, images of various mask systems may be overlaid to determine how well a mask system fits. In still other embodiments, a user can hold a transparency corresponding to a mask design in front of the patient's face to determine how well a mask system fits.