Urban areas are large complex diverted systems including two categories of objects: natural and man- made. Natural objects include trees, rivers, shorelines, etc. Man-made objects include buildings, roads, bridges, etc. The spatial distribution of the previous objects, particularly buildings, is one of the most important data sources for information technology-based applications such as environmental monitoring, intelligent transportation system, telecommunications, urban planning, and mobile communications. The development of an automated algorithm for producing city models is of great necessity since manual operations are very costly and time consuming. This book presents a noval technique to detect and delineate 3D buildings with complex rooftops by extracting and matching roof polygons in high-resolution remotely-sensed aerial images.