Singapore is a unique polity in the world and in Southeast Asia. A survey conducted at the National University of Singapore (NUS) of perceptions generally of countries worldwide and specifically of the Association of Southeast Asian Nations (ASEAN) demonstrates a sense of Singaporean exceptionalism. While respondents to the survey have a distinct sense of ASEAN as a regional grouping, they see Singapore as largely apart from rather than a part of Southeast Asia. The article examines the results from Singapore, with reference to comparable surveys carried out in four other ASEAN member states. The unique sense of Singaporean exceptionalism is attributed to Singapore's own unusual characteristics, struggles with national identity, and overriding economic imperatives associated with nation survival. This sense of exceptionalism exemplifies challenges to ASEAN integration that are not only of relevance to Singapore but to the region generally.