Epilepsy is common in people with intellectual and developmental disabilities (IDD). In adulthood, patients with IDD and epilepsy (IDD-E) have neurologic, psychiatric, medical, and social challenges compounded by fragmented and limited care. With increasing neurologic disability, there is a higher frequency of epilepsy, especially symptomatic generalized and treatment-resistant epilepsies. The causes of IDD-E are increasingly recognized to be genetic based on chromosomal microarray analysis to identify copy number variants, gene panels (epilepsy, autism spectrum disorder, intellectual disability), and whole-exome sequencing. A specific genetic diagnosis may guide care by pointing to comorbid disorders and best therapy. Therapy to control seizures should be individualized, with drug selection based on seizure types, epilepsy syndrome, concomitant medications, and comorbid disorders. There are limited comparative antiepileptic drug data in the IDD-E population. Vagus nerve and responsive neural stimulation therapies and resective surgery should be considered. Among the many comorbid disorders that affect patients with IDD-E, psychiatric and sleep disorders are common but often unrecognized and typically not treated. Transition from holistic and coordinated pediatric to adult care is often a vulnerable period. Communication among adult health care providers is complex but essential to ensure best care when these patients are seen in outpatient, emergency room, and inpatient settings. We propose specific recommendations for minimum care standards for people with IDD-E. Living with intellectual and developmental disabilities (IDD) and epilepsy (IDD-E) holds challenges for the individual, caregivers, and family. Activities of daily living and quality of life (QOL) can be affected by comorbid physical, mental, or cognitive disabilities, as well as epilepsy. Despite progress in care, many problems persist, including a failure to provide medical student and resident education about IDD-E populations. Current adult epilepsy services are often unable to adequately address the needs of this population, who face disparities in health care. Medical science has failed to provide evidence-based data on the care of patients with IDD-E. Randomized controlled trials are needed.This article, based on a workshop, highlights areas where a greater understanding of the issues and an application of current knowledge could improve the quality of care and QOL in the IDD-E population. We identify areas in which a change in clinical management should be considered and recommend minimum care standards that have excellent face validity but are not evidence-based, reflecting a paucity of rigorous research in this population.FOCUS ON MANAGEMENT CHANGE The following key questions can be asked of the neurology community, to which a positive answer would undoubtedly lead to major improvements in care of adult patients with