Abnormal electrical conduction and excitability associated with fibrosis in the left atrium (LA) may serve as a substrate for atrial fibrillation (AF). Electroanatomical voltage mapping systems (EAMs) have become a dominant facilitator to treat AF with surgical ablation assisted by additional diagnostic imaging modalities. Importantly, AF has been associated with structural changes to the extracellular matrix of the myocardium, including increased collagen deposition -a process known as fibrosis. Late gadolinium-enhanced magnetic resonance imaging (LGE-MRI) may aid in guiding AF cardiac ablation therapy by determination of fibrosis in the LA. To locate fibrosis for cardiac ablation, however, precise registration between EAMs andLGE-MRI data is crucial. The purpose of this thesis was to develop a method for registering EAMs with late gadolinium-enhanced magnetic resonance image (LGE-MR) images. Twenty patients with persistent AF, who underwent magnetic resonance imaging scanning and EAMs prior to first-time catheter ablation, participated in the study. An experienced radiologist manually segmented the boundaries of the LA onLGE-MR images. In our registration pipeline, the first step involved manual alignment of the LGE-MR images to the left atrial surface on EAMs. The iterative closest point (ICP) algorithm was then applied to deform the left atrial surface determined using LGE-MRI to that of EAMs in an affine manner. We then applied a non-rigid iv ICP (NICP) algorithm to correct for non-linear deformations. The results demonstrate that NICP provided a substantial reduction in target registration error when compared to the use of affine ICP alone. v Dedication With warm and sincere thanks to Prof. Eranga Ukwatta for his superb guidance and feedback on technical image analysis; Dr. Rebecca E. Thornhill for her tireless research, insightful guidance on editing; Prof. Andy Adler for his supervision; Dr. Pablo Nery for initiating the research project; Dr. Robert DeKemp for offering his laboratory to support my research.Thanks also to the biomedical engineering laboratory colleagues who helped me go through the M.A.Sc graduate study with great understanding as well as for their friendship; Carleton University for giving me the opportunity to achieve M.A.Sc degree.