Over the years we have been able to successfully apply technology at our convenience in the fields of surgery, without exception in reconstructive plastic surgery. These are computer-aided design (CAD) and virtual surgical planning for different procedures in various specialties. Currently it is possible to acquire high-resolution images with different methods for the recognition and distinction of organs and tissues in high resolution, allowing high-precision three-dimensional reconstructions. In this chapter the reader will learn to differentiate the concepts of virtual reality and augmented reality, as well as the necessary steps to select different regions of interest (ROI), or also called segmentation process through open source software. As well as the processes involved from obtaining the images of the slices in DICOM (Digital Imaging and Communications in Medicine) to the virtual three-dimensional reconstruction process. Finally, through a virtual three-dimensional figure it is possible to obtain a three-dimensional solid model using different materials, according to convenience, through the computer aided manufacturing (CAM) method, especially useful for high complexity surgeries or for resident training. This state-of-the-art approach to complex lower extremity reconstructions is detailed through examples of preoperative planning and marking of SCIP (superficial circumflex iliac artery perforator) flap donor site using augmented reality, three-dimensional biomodel impression and cutting guide for intraoperative use in lower extremity reconstruction, and example of virtual planning for mapping perforators of anterolateral thigh flap.