In this chapter, we review the research on parenting and family relationships of children and adolescents with ADHD. This research clearly demonstrates that ADHD in children, adolescents, and parents impacts the entire family system. Compared to families of neurotypical children, families of children and adolescents with ADHD are usually less cohesive and organized, and parent/child, co-parent, and sibling relationships are more conflictual. Parents of children and adolescents with ADHD experience high levels of parenting stress and are more likely than parents of neurotypical children to engage in negative parenting behaviors. Negative parenting behaviors are associated with parenting stress, low parenting self-efficacy, parent ADHD, and parent mental health challenges, including anxiety and depression. Because ADHD impacts the entire family system, assessments should include examining parent and family relationships in addition to child ADHD and impairments. Fortunately, there are several helpful interventions that are supported by high-quality research. All of these interventions require some level of parent involvement.