This paper focuses on designing a comprehensibility test and a questionnaire for spoken world Englishes in Brunei, Malaysia, the Philippines and Singapore, and utilizing the test to investigate the comprehension of Burmese, Cambodians, Indonesians, Laotians, Thais and Vietnamese. We reviewed the demarcation of users of English based on Kachru's (1984, 1985) three concentric models within the bloc's context where two circles--Outer Circle and Expanding Circle are present. The findings established a moderate comprehensibility level of Expanding Circle listeners toward the speakers of the Outer Circle. The variations of comprehensibility scores paved way for the exploration of the comprehension scores' possible relationships with language proficiencies, attitudes toward speakers, familiarity of spoken variety, historical origins of languages, and political ambiance between and among ASEAN nations. (Contains 8 tables and 1 figure.) [Work on this paper was partly supported by Prince of Songkla University's Graduate School Grant.]