The objective of this investigation is to develop a geometric correction system for multiple satellite imagery. There are two major components in this research: (1) ortho-rectification, and (2) image mosaicing. In order to process the different sensors with different geometric models, this system employs a multi-sensor approach. The geometric model includes rigorous sensor model (RSM) and rational function model (RFM) in the sensor modeling. The flexibility of orientation modeling can be considered as scene-based, strip-based and block adjustment. The multi-strip block adjustment includes Digital Elevation Model to overcome the problem of weak geometry between images. As image mosaicing is an important task, we also develop a procedure for seamline selection and color balance.