The authors of the current study examined the relationships among item-recognition, source-recognition, free recall, and other memory and cognitive ability tasks via an individual differences analysis. Two independent sources of variance contributed to item-recognition and source-recognition performance, and these two constructs related differentially to other memory and cognitive ability constructs. The results are in accordance with a dual-process theory of memory retrieval in which a familiarity process can support judgments of previous occurrence and a more strategic recollection process is needed for controlled search of long-term memory. Furthermore, the authors offer additional evidence in favor of a dual-process model by showing validity for these two unique sources of variance. (Contains 2 tables, 2 figures and 4 footnotes.)