Few qualitative studies have focused on the experiences of students with attention-deficit/hyperactivity disorder (ADHD) pursuing postsecondary education, and in particular, how their academic difficulties manifest themselves. This study provides a better understanding of how ADHD affects students in their studies. In-depth interviews were conducted with 29 college and university students with ADHD, their relatives (n = 26), and their counselors (n = 9). Participants reported significant academic impairment (e.g., difficulties related to attention, emotional regulation, motivation, time management, inhibition, working memory, organization, and planning) and a complex relationship with the ADHD label. The difficulties experienced by students seem to be closely related to deficits in executive functions. This interrelation complicates the understanding of functional impairment. Implications for practice provide recommendations based on the literature on how to improve the academic success of students with ADHD in postsecondary education.