Eligibility for Early Intervention Services varies by country and region, but in general, infants and toddlers who show developmental delays or have a diagnosed physical or mental condition that increases the likelihood of developmental delays may be eligible for such services. This can include children with a delay of 25 percent or more in one or more areas of development or those that have been diagnosed with a condition that affects development such as Downs syndrome. Eligibility typically requires a diagnosis by a specialist, such as a physician or psychologist. The specific criteria and process for determining eligibility may vary, and families are encouraged to consult with their healthcare provider or local early intervention program for more information.