Recognition memory is supported by recollection of qualitative information about previous study events and by assessments of stimulus familiarity. Results from behavioral, neuropsychological and neuroimaging studies are reviewed that aim to determine the operating characteristics of these forms of memory and uncover their neural substrates. Various methods have been developed to measure these two forms of memory and have indicated that recollection and familiarity are functionally independent at both encoding and retrieval. Moreover, neuropsychological and neuroimaging results indicate that they rely on partially distinct brain regions.