Person recognition systems that consolidate evidence from multiple sources of biometric information in order to determine the identity of an individual are known as multibiometric systemsMultibiometrics. For example, face and iris traits, or fingerprints from all ten fingers of an individual, may be used together to accurately and robustly resolve the identity of the person. Multibiometric systems can overcome many of the limitations of unibiometric systems because the different biometric sources usually compensate for the inherent limitations of one another. Hence, multibiometric systems are generally expected to be more reliable and accurate than unibiometric systems, as well as provide a wider population coverage (reduce the failure to enroll rate). The process of consolidating the information or evidence presented by multiple biometric sources is known as information fusionInformation fusion, which is the main focus of this chapter. More specifically, this chapter introduces the different sources and types of biometric information that can be fused and the various fusion methodologies.