As used in this subchapter: (1) At-risk infant or toddler The term "at-risk infant or toddler" means an individual under 3 years of age who would be at risk of experiencing a substantial developmental delay if early intervention services were not provided to the individual. (2) Council The term "council" means a State interagency coordinating council established under section 1441 of this title. (3) Developmental delay The term "developmental delay", when used with respect to an individual residing in a State, has the meaning given such term by the State under section 1435(a)(1) of this title. (4) Early intervention services The term "early intervention services" means developmental services that - (A) are provided under public supervision; (B) are provided at no cost except where Federal or State law provides for a system of payments by families, including a schedule of sliding fees; (C) are designed to meet the developmental needs of an infant or toddler with a disability in any one or more of the following areas - (i) physical development; (ii) cognitive development; (iii) communication development; (iv) social or emotional development; or (v) adaptive development; (D) meet the standards of the State in which they are provided, including the requirements of this subchapter; (E) include - (i) family training, counseling, and home visits; (ii) special instruction; (iii) speech-language pathology and audiology services; (iv) occupational therapy; (v) physical therapy; (vi) psychological services; (vii) service coordination services; (viii) medical services only for diagnostic or evaluation purposes; (ix) early identification, screening, and assessment services; (x) health services necessary to enable the infant or toddler to benefit from the other early intervention services; (xi) social work services; (xii) vision services; (xiii) assistive technology devices and assistive technology services; and (xiv) transportation and related costs that are necessary to enable an infant or toddler and the infant's or toddler's family to receive another service described in this paragraph; (F) are provided by qualified personnel, including - (i) special educators; (ii) speech-language pathologists and audiologists; (iii) occupational therapists; (iv) physical therapists; (v) psychologists; (vi) social workers; (vii) nurses; (viii) nutritionists; (ix) family therapists; (x) orientation and mobility specialists; and (xi) pediatricians and other physicians; (G) to the maximum extent appropriate, are provided in natural environments, including the home, and community settings in which children without disabilities participate; and (H) are provided in conformity with an individualized family service plan adopted in accordance with section 1436 of this title. (5) Infant or toddler with a disability The term "infant or toddler with a disability" - (A) means an individual under 3 years of age who needs early intervention services because the individual - (i) is experiencing developmental delays, as measured by appropriate diagnostic instruments and procedures in one or more of the areas of cognitive development, physical development, communication development, social or emotional development, and adaptive development; or (ii) has a diagnosed physical or mental condition which has a high probability of resulting in developmental delay; and (B) may also include, at a State's discretion, at-risk infants and toddlers.