Objective: An ecologically valid adaptation of the irrelevant sound effect paradigm was employed to examine the relative roles of short-term memory, selective attention, and sustained attention in ADHD. Method: In all, 32 adults with ADHD and 32 control participants completed a serial recall task in silence or while ignoring irrelevant background sound. Results: Serial recall performance in adults with ADHD was reduced relative to controls in both conditions. The degree of interference due to irrelevant sound was greater for adults with ADHD. Furthermore, a positive correlation was observed between task performance under conditions of irrelevant sound and the extent of attentional problems reported by patients on a clinical symptom scale. Conclusion: The results demonstrate that adults with ADHD exhibit impaired short-term memory and a low resistance to distraction; however, their capacity for sustained attention is preserved as the impact of irrelevant sound diminished over the course of the task. (J. of Att. Dis. 2013; XX(X) 1-XX)