This paper discusses the use of an alternative instrument to assess the social-emotional competence (SEC) of secondary school students in Singapore. The instrument was used in a larger study to explore an approach to infuse social-emotional learning in the curriculum for children in school. The design of this research instrument is based on the Rest's (Development in judging moral issues. University of Minnesota Press, Minneapolis, 1979) Defining Issues Test (DIT) originally developed based on Kohlberg's moral dilemma (Kohlberg in child psychology and childhood education: a cognitive developmental view. Longman, New York, 1987). The modified DIT instrument which focuses specifically on social-emotional development presents scenarios that are most likely encountered by adolescents and seeks the students' responses to five open-ended questions related to the scenarios. The verbatim written responses were coded and categorized to assess their SECs. The instrument was able to elicit the self-management strategies of the secondary students, which was not as easily assessable with alternative instruments measuring SECs. The findings also highlighted the psychosocial developmental stage and moral development of the adolescents in the study from the SEC responses that they made.