There is an increasing support from international organizations and the research community for stepping beyond infant or child mortality as the most common child level social indicator and progressing towards an international measure of child development. The Early Development Instrument (EDI) is a teacher-completed measure of children's developmental health at school entry, which to date has been used in more than a dozen countries. The EDI includes five developmental domains (Physical Health and Well-being, Social Competence, Emotional Maturity, Language and Cognitive Development and Communication Skills and General Knowledge) and 16 subdomains. This paper examines the EDI's psychometric properties in four English-speaking countries (Canada, Australia, United States and Jamaica) by evaluating both the internal consistency and factor structures, as well as exploring the association between the EDI's Language and Cognitive Development Domain and a direct assessment of children's receptive vocabulary (Peabody Picture Vocabulary Test, PPVT). Overall, the factor loadings and internal consistencies of domains and subdomains were similar across the countries. The comparisons of the Language and Cognitive Development Domain with the PPVT showed high specificity and low sensitivity. The results of this paper indicate that the EDI, a measure of children's developmental status at school entry, demonstrates similar psychometric properties in a number of countries, thus building the evidence for the instrument to be added to the limited array of internationally comparable child social indicators.