School readiness assessments in South Africa still predominantly focus on the assessment of cognitive skills. The Emotional Social Screening Tool for School Readiness (E3SR) was developed to bridge the perceived gap in assessing emotional-social skills as a domain of school readiness. An emerging body of research reports exists on the psychometric properties and factor structure of the E3SR. An initial validation study recommended a 6-factor solution instead of the theoretical 9-factor model that was proposed in the development of the E3SR. The E3SR (Revised) was also reduced in length. We report here on a pilot study of which the aim was to establish the reliability and construct validity of the E3SR (Revised). A cross-sectional survey design was used to gather data from 9 pre-schools in Cape Town, South Africa. Pre-school teachers (n = 24) constituted the respondent group who completed the E3SR (Revised) screening questionnaires on Grade R learners (n = 394). Analysis was conducted on 321 completed screening questionnaires. With the data analysis we aimed to: a) summarise sample characteristics of teachers and children; b) establish reliability estimates; and c) establish construct validity and confirming the factor structure. Ethics clearance was given by the Humanities and Social Science Research Ethics Committee (HSSREC) of the University of the Western Cape. The study adhered to stipulated ethics requirements. Data failed to show multivariate normality; however, this violation of normality was expected and was theoretically supported. The sample size (n = 321) was sufficient for factor analysis of a 36-item scale. All subscales showed excellent reliability: Cronbach's alphas ranged between 0.939 and 0.971. CFA results demonstrated a good model fit. The E3SR (Revised) was found to be reliable and valid for use. The use of a rigorous methodological process including the decision-making matrix represent good research practice that can be used in instrument development across cultures.