The two studies reported in this paper comprise the Turkish Early Enrichment Project (TEEP) spanning a period of 10 years. Both studies were conducted with mothers and children in low-income, low-education areas of Istanbul. Study I involved an examination over 4 years of the effects of two different types of early enrichment (intervention), child-focused (center-based) and mother-focused (home-based). Study 2 was a follow-up of Study 1, 7 years after the end of project intervention. Although both interventions produced superior cognitive skills and school adjustment at the end of the program, follow-up assessments in Study 2 revealed that parent-focused intervention had numerous sustained effects in terms of school attainment, higher primary school grades and vocabulary scores, more favorable attitudes towards school, and better family and social adjustment, while most effects of center-based intervention had dissipated (with the notable exception of negative effects of custodial, as opposed to educational, day care). It is concluded that home-based early enrichment through the mediation of the mother is a highly effective strategy with multiple positive outcomes in contexts of socioeconomic disadvantage. (C) 2001 Elsevier Science Inc. All rights reserved.