Computer–based working memory training exercises produce improvements in performance on ability measures that are similar to the trained tasks (near-transfer), but results have been inconsistent regarding generalization of training outcomes to other abilities and behaviors, particularly those reflecting symptoms of attentiondeficit/hyperactivity disorder (ADHD). In contrast to the growing body of efficacy research in this area, almost no studies have systematically investigated characteristics of subjects that predict response to working memory training. This study is an investigation of subject characteristics that predicted change in near-transfer immediate memory span performance following working memory training. Children and adolescents aged 9-16 years (N=62) with a broad range of reported symptoms of attention-deficit/hyperactivity disorder (ADHD) completed working memory training for a 25-day period. Assessments of verbal and visual working memory span and ADHD symptoms were completed at the beginning and end of working memory training. Greater improvement in working memory span from baseline to post-training was predicted by poorer memory span, more hyperactivity-impulsivity symptoms, and fewer inattention symptoms at the baseline. For baseline memory span and hyperactivity-impulsivity symptoms, study results are consistent with a remediation or rehabilitation mo del in which working memory training produces more near-transfer improvement for individuals who have more baseline delay or impairment. However, the opposite relationship was found for inattention, perhaps because poor attention skills interfere with the ability to actively engage in working memory training. Clinically, this information may be useful for identifying individuals who are more likely to benefit from working memory training.