This is the first unit in a series of instructional materials arising from an exploratory study of cultural barriers to communication between North Americans and Colombians. A syllogistic model, in which our unspoken and unconscious assumptions comprise the major premise, is used to explain the difficulties of intercultural communication. These silent assumptions are revealed and explained through the material presented, which consists of (1) a physical description of Bogota, highlighting the foreigner's first impressions, (2) the experiences and impressions of one composite North American student upon arrival in the city, and (3) a case study of a cross-cultural misunderstanding involving the Colombian family unit. An appendix lists idioms peculiar to Colombian Spanish. For companion documents, see the original exploratory study, FL 001 088 and Unit 2 of the instructional materials, FL 001 089. (DS)