For two years after birth, maternal engagement with the child, maternal validation, and problem solving were central targets, as were parenting skills more generally. Parents were encouraged to utilize agencies and programs for financial, social, and educational support. Importantly, mothers were encouraged and assisted to develop job skills.
The program has been replicated in rigorous randomized studies, and follow-up studies have been conducted for up to 15 years. A wide variety of immediate impacts on early child behavior and cognitive development have been reported, as well as important long-term effects on behavioral adjustment. In addition to direct effects on child development and parenting, the mothers in the intervention groups had fewer and more widely spaced pregnancies and were significantly more likely to get paying jobs and to leave welfare. Beyond demonstrating the potential of early intervention with parents, the program also demonstrates the wide range of serious risk factors that are malleable in high-risk families with young children.
A variant of this model, called Healthy Start, originated in Hawaii and now operates in 37 or 38 states; it appears effective and feasible for largescale prevention efforts. To date there have been no randomized trials of Healthy Start.
The basis for early and secure emotional attachment between mother and child has long been considered the foundation on which the psychological, emotional, and social development of the child is built. Insecure attachment has been implicated in both ineffective, harsh, and neglectful parenting and in the development of externalizing behavior by young children. A large number of studies of the efficacy of interventions designed to improve attachment has been carried out with mixed results. A classic study by van den Boom (1994) showed dramatic effects of early intervention both on the mother (contingent responsiveness, sensitivity) and on the infant (secure attachment, sociability, self-soothing, exploration). These findings were partially replicated by Toth et al. (2000) and by Wendland-Carro (1999). Although the long-term effects of attachment-focused interventions are not yet clear, they reliably increase maternal sensitivity and engagement, which are key factors in the prevention of emotional-behavioral problems. For a review and meta-analysis of relevant studies, see van Ijzendoorn et al. (1995).
The key developmental challenges during the preschool period expand to include demands for increased impulse control and compliance to social