Prior to 1986, many speech-language pathologists serving infants and toddlers with communication disorders used an expert service delivery model. In the expert model, the speech-language pathologist is viewed as the professional who provides solutions by way of direct intervention to a child. Service delivery is often direct, and families have little control over the focus of and method of intervention. However, with passage of Public Law 99-457, a shift in service delivery philosophies occurred, with a new emphasis on a family-centered model (Donahue-Kilburg, 1992).

PL 99-457, Part H, mandated comprehensive, coordinated, community-based and family-centered services for infants and toddlers exhibiting disabilities in physical, cognitive, communication, social or emotional, and/ or adaptive development. A range of services, including speech-language services and audiology, are available at no cost to the parents except where federal or state law provides for a system of payment by families. Reauthorization of IDEA in 1997 led to a change in name (now referred to as Part C). The reauthorization emphasizes services to children in natural environments (i.e., locations where the child would be served if he or she did not have a disability), using family-directed service delivery to identify family needs, and affirms families as members of the evaluation team.

Interagency coordinating councils (ICCs) exist at the federal, state, and local levels. Eligibility criteria for early intervention services under Part C is decided by each state's lead ICC, and as a result, varies from state to state. Eligibility is often determined by the presence of a developmental delay in physical, cognitive, speech and language, social or emotional, and adaptive (i.e., self-help) skills; or eligibility may be based on the degree of risk that the child has for developing a delay. There are three types of risks: established risk, biological risk, and environmental risk. In the case of established risk, a child displays a diagnosed medical condition, such as Down syndrome, fragile X syndrome, or Turner's syndrome, that is known to influence development negatively. Children with an established risk qualify for early intervention services. In contrast, a child who is biologically at risk exhibits characteristics (e.g., very low birth weight, otitis media, prematurity) that may result in developmental difficulties. A child with an environmental risk is exposed to conditions that may interfere with normal development, such as poor nutrition, poor environmental stimulation, or caregivers with substance abuse problems. Children with biological or environmental risks are considered to be at risk rather than to have an established risk. Some states include children who are at risk in their eligibility criteria for services; others do not.

One group of toddlers seen by speech-language pathologists who have been studied extensively display slow expressive language development (SELD). SELD is characterized by an expressive vocabulary of less than 50 words at 24 months of age and no word combinations, with no known hearing, cognitive, emotional/ behavioral, gross neurological, oral-motor, or environmental deprivation (Rescorla, 1989; Paul, 1993). Paul (1996) concluded that children with SELD should not be regarded as having a disorder; rather, they should be considered at risk for further language impairment. Her longitudinal study of children identified as having SELD indicated that approximately 74% of the children identified with SELD as toddlers were no longer classified as having an expressive language delay by kindergarten age. Paul recommended a “watch-and-see” policy for children with SELD who do not display other risk factors. The watch-and-see policy would monitor children on a regular basis for their linguistic progress. However, other researchers have opposed such a policy, for a variety of reasons (van Kleeck, Gillam, and Davis, 1997). Children with specific language impairment (SLI), which can include receptive and expressive language skills, may also be seen for early intervention services. Risk factors for SLI include heredity, long periods of untreated otitis media, and parental characteristics such as low socioeconomic status, directive interaction style, and extreme parental concern (Olswang, Rodriquez, and Timler, 1998).

The family plays a vital role in providing services to infants and toddlers with communication disorders. They are part of the team from the referral stage through assessment, intervention, and dismissal. It is critical to consider the cultural variables that contribute to each family's unique system of functioning when working with families of infants and toddlers with communication disorders. The speech-language pathologist should understand each family's cultural belief system as it applies to views about disabilities, communication behaviors, and childrearing. Adopting a family-guided approach to early intervention requires a nonjudgmental respect for the family's views. The first step to understanding and respecting family and cultural views is to understand one's own family and culture. This places the speech-language pathologist in a position to understand differences of opinion and reduce potential misunderstandings. The next step is to learn about the family's belief system by observing, listening, and sharing information. Skills in interviewing and counseling are crucial for obtaining and clarifying information in a nonthreatening and respectful manner.

Unlike the expert model, which focuses only on the client's needs, the family-guided model focuses on both the family and the child. Child assessment and family assessment may both take place. A family assessment is voluntary and often conducted through interviews and surveys designed to collect information about the family's resources, priorities, and concerns. Child assessments must be multidisciplinary and comprehensive, conducted by trained personnel, and include both strengths and weaknesses of the child. The assessment should also be nondiscriminatory and confidential. Informed consent must be obtained. Professionals have 45 days from screening to complete the evaluation process that may determine the presence of a disorder and determine eligibility.

Assessment of infants and toddlers includes a variety of tasks and a range of informational questions asked of family members. Areas assessed include infant state behaviors, respiration, oral-motor skills (including sucking and swallowing evaluations), nonverbal communication behaviors, play behaviors, caregiver-child interaction, receptive and expressive vocabulary skills, phonological skills, word combinations, syntactic development, functions for language use, and cognitive skills (Donahue-Kilburg, 1992; Dickson, Linder, and Hudson, 1993; Paul, 2001). Assessment in the neonatal intensive care unit may involve working with nurses and parents and revolves around making the environment as positive as possible for the infant (Ziev, 1999). Assessment includes formal, standardized tests, informal methods such as play-based assessment and temptation tasks, and parental report.

Often assessment is conducted in an arena format, where one member of the team serves as the primary facilitator. Other team members observe and make notes about the child's behavior in their specialty area. In a transdisciplinary arena assessment, the primary facilitator will adopt the roles of the other professionals. Families can be involved in assessment by providing information, observing and collecting information, and interacting with their child. The level of involvement is the family's choice. It is important to remember that families are dynamic systems and that roles and functions of family members can change. A family initially reluctant to participate may want to participate in the next session. Frequent communication is necessary to ensure that services remain family-guided and family-friendly.

Families also assist the speech-language pathologist in determining outcomes rather than goals. These outcomes can be child-oriented, family-oriented, or both. The outcomes are written in family-friendly language, often in the family's own words. These outcomes are written in the form of an Individual Family Service Plan (IFSP). Importantly, the IFSP is a process as well as document. The process begins at referral and involves getting to know the family and child. It is an informal transferal of information that builds the foundation of trust and respect underlying future interactions. The written IFSP will contain information about the person who serves as the family service coordinator, the child's status in the areas of physical, cognitive, communication, social-emotional, and adaptive development, a plan that indicates the frequency and length of services, who will pay for services, the method of providing services, and how service will be provided in natural environments. The family service provider is selected by the family and is the main coordinator of services. The IFSP also includes a transition plan for children leaving Part C services and entering preschool (or Part B) services. It is optional on the part of the family whether or not they want the IFSP to contain information on the family's resources, concerns, and priorities. IFSPs can be used for children ages 0–6 years. Thus, on transitioning to Part B services, families may choose an IFSP instead of an Individual Education Plan.

Once outcomes have been selected, the type of intervention approach is determined. It is important to understand the family's view of speech and language development and the role they believe they play in their child's development of speech and language. Family members may choose to play an integral role in the intervention; others may prefer to have the intervention conducted by the speech-language pathologist. Intervention studies thus far have provided evidence that early intervention with infants and toddlers can facilitate prelinguistic behaviors, expressive vocabulary, phonology, social skills, and early word combinations (Girolametto et al., 1996, 1997, 1999; Robertson and Ellis Weismer, 1999; Yoder and Warren, 1998; Loeb and Armstrong, 2001). Some child-oriented techniques include parallel talk, recasting, and expansions. Some interventions focus modeling language effectively in everyday routines and scripts. The ultimate goal of this early intervention for children with established risk and those who are at risk is to reduce the likelihood that they will require future intervention and special education services and will gain the skills needed to participate socially and academically as they grow.

See also speech disorders in children: birth-related risk factors.