Alongside pharmacotherapy, cognitive-behavioral therapy (CBT) is the second evidence-supported treatment for attention-deficit/hyperactivity disorder (ADHD) in adults. ADHD is increasingly understood as a disorder of poor self-regulation. This core difficulty creates the many downstream functional impairments associated with a lifetime diagnosis of ADHD. CBT targets the procrastination, disorganization, poor time management, and so forth that create the problems in daily life for which ADHD adults seek help, particularly emphasizing skills-based behavior change and skills performance. The relevance of the cognitive domain of CBT for adult ADHD has often been viewed as limited to the degree to which it is needed to treat comorbid depression or anxiety. However, recent research and treatment approaches highlight the relevance of cognitive distortions in the conceptualization and psychosocial treatment of adult ADHD. The aim of this paper is to review the recent and converging research on the impact and clinical relevance of cognitive distortions and other mindsets in understanding and treating adults with ADHD. A review of the contemporary model of ADHD as a problem of self-regulation and the associated functional impairments points to the need for comprehensive treatment. The empirical support for CBT adapted for adult ADHD as the psychosocial treatment of choice will then be briefly reviewed, augmented with emerging research highlighting cognitive distortions in samples of adults with ADHD. Lastly, clinically relevant examples of cognitive interventions used in CBT for adult ADHD will be presented to tie together research and clinical practice.