One of the most important features of any early intervention system is the ability to effectively and efficiently find children with developmental problems or to identify conditions and circumstances that are likely to give rise to later problems. In the first instance, comprehensive early intervention programs can be initiated as early as possible; in the second, preventive interventions can be organized in order to minimize the possibility of future developmental difficulties. Despite their importance, the screening and identification components of early intervention systems in many, if not most, communities are far from ideal. The reasons for this are numerous, including the absence of reliable and valid tools for many domains of development, difficulties adjusting to the probabilistic nature of the screening process, problems coordinating information from the many community agencies and professionals involved in screening, and the lack of community leadership to establish agreed upon protocols within a systems framework. Issues relating to the unevenness of children's development further compound the problem and require a carefully thought through process of monitoring.

A number of articles in this issue of Infants and Young Children are concerned with this important problem. Included is a discussion of the use of registries for children with primarily structural birth defects to help identify those with developmental problems warranting early intervention. As noted, the reliability and validity of screening tools is a concern, especially for very young children. Two articles address this issue, one focusing on screening infants between 3 and 12 months of age for neuromotor as well as cognitive/behavioral concerns; the other seeking to better identify children younger than 2 years of age who will develop communication disorders. A fourth article considers factors that are helpful in predicting children's cognitive development in low-income families. This information can guide practitioners in their preventive intervention efforts.

Other articles in this issue focus on diverse areas of interest to those of us working closely with young vulnerable children and their families. Specifically, the topic of emotional expression, especially facial expression, is examined in considerable detail. The facial expressions of young children can serve as a unique source of vital information for practitioners and families alike. In addition, the ongoing concern of otitis media with effusion on hearing and language development is explored specifically in connection with children with established developmental disabilities. Suggestions for early interventions to minimize any adverse effects are provided. Finally, a discussion is presented of the value and limitations of guiding early interventions based on knowledge of a child's specific genetic etiology. The important concept of "behavioral phenotypes" is considered along with its broad developmental influences.