Brain templates define a common coordinate system for analysis. These templates facilitate processing and take advantage of prior information. Image registration is a critical part of template generation process which is focused in this book. Image registration is the process of aligning images of the same scene taken at different times, from different viewpoints or by different sensors. The reviewed approaches are classified according to their nature (area based and feature based) and according to four basic steps of image registration procedure: feature detection, feature matching, mapping function design, and image transformation and resampling. Main contributions, advantages, and drawbacks of some of the new image registration methods, including a new suggested approach based on line detection and mapping, are discussed in this study. Various issues of image registration and outlook for the future research are discussed too. The major goal of this work is to do a comprehensive study on image registration as a part of template creation techniques related to brain imaging application areas and present a comparative analysis of proposed approach with existing techniques.