Stimuli presented with targets during a monitoring task are better remembered than stimuli presented with distractors, a result referred to as the attentional boost effect (ABE). The ABE is consistently found for item memory, but conflicting results have been reported for different assessments of associative memory, with studies of source memory (whether the study item had been presented with a target or distractor) demonstrating an ABE and studies of context memory (memory for the perceptual details or list membership of the study item) not showing the effect. This could be due to methodological differences across studies (study materials: pictures vs. words; number of study presentations: multiple vs. single), issues related to the measurement of source memory (traditional measures vs. multinomial modeling), or differences in the informational bases of source and context memory tests. Three experiments consistently found an ABE in source memory and ruled out differences based on study materials, number of study presentations, and technique for measuring source memory. The discrepancies in the prior research appear to hinge on the differences in informational bases of source and context memory tests. In particular, source memory relies on associations between the study item and information about the monitoring task and is open to inferential processes (participants exhibit a significant bias to categorize false alarms as coming from the distractor condition).