A survey was conducted to determine states' progress towards developing a definition for developmentally delayed infants and toddlers as required by Public Law 99-457, Part H. Results of the survey, conducted in the summer of 1988, indicated that many states had made a great deal of progress toward developing a policy regarding the definition of developmentally delayed, most states had only partially completed the process, and a few had not yet begun. The Interagency Coordinating Council and the lead agency were identified as playing a major role in providing input into this process. A content analysis of the completed definitions from 28 states showed that all definitions included developmentally delayed infants and toddlers and those with established risk. Three major types of eligibility criteria were prominent: percent delay, delay in number of months, and delay as indicated by standard deviation. Within these major areas, there was considerable variance in the level of delay needed to establish eligibility for services. Over half of the states included at-risk infants and toddlers, but there was minimal agreement as to which factors place a child at risk, with 53 different biological criteria and 36 environmental risk factors being cited by states using these categories in forming definitions. (JDD)