Developmental delays, disorders, or disabilities (DDs) manifest in infancy and childhood and can limit a person's function throughout life* (1-3). To guide strategies to optimize health for U.S. children with DDs, CDC analyzed data from 44,299 participants in the 2014-2018 National Health Interview Survey (NHIS). Parents reported on 10 DDs,† functional abilities, health needs, and use of services. Among the approximately one in six (17.3%) U.S. children and adolescents aged 3-17 years (hereafter children) with one or more DDs, 5.7% had limited ability to move or play, 4.7% needed help with personal care, 4.6% needed special equipment, and 2.4% received home health care, compared with ≤1% for each of these measures among children without DDs. Children with DDs were two to seven times as likely as those without DDs to have taken prescription medication for ≥3 months (41.6% versus 8.4%), seen a mental health professional (30.6% versus 4.5%), a medical specialist (26.0% versus 12.4%), or a special therapist, such as a physical, occupational, or speech therapist, (25.0% versus 4.5%) during the past year, and 18 times as likely to have received special education or early intervention services (EIS) (41.9% versus 2.4%). These percentages varied by type of disability and by sociodemographic subgroup. DDs are common, and children with DDs often need substantial health care and services. Policies and programs that promote early identification of children with developmental delays and facilitate increased access to intervention services can improve health and reduce the need for services later in life.§ Sociodemographic inequities merit further investigation to guide public health action and ensure early and equitable access to needed care and services.