This Book is focused on the combination of multiple biometric trait for person authentication in what called as multimodal biometric system. In this book, multimodal biometric system integrating face and ear at feature level is proposed. Feature Extraction is done by PCA and FLD. Multimodal biometric systems elegantly address several of the problems present in unimodal systems. By combining multiple sources of information, these systems improve matching performance, increase population coverage, deter spoofing, and facilitate indexing. Various fusion levels and scenarios are possible in multimodal systems. Incorporating user-specific parameters can further improve performance of these systems