People with intellectual and developmental disabilities (IDD) frequently have behavioral or mental health needs, but experience obstacles to treatment. Family caregivers are often responsible for coordinating the care of individuals with IDD. This study examined family caregiver experiences using intake data from a national tertiary crisis intervention model designed for people with IDD and mental health needs. Caregivers (n = 488) completed the Family Experiences Interview Schedule. Less than half of families reported satisfaction with the mental health services received. Notable gaps were in crisis, night and weekend services, choice of services and providers, communication and coordination between providers, and specialized training. Experiences were worse for caregiving fathers and individuals with IDD with co-occurring chronic medical conditions.