American English and British English vocabularies have diverged over time, result, ing in lexical differences that have the potential to confound English-language intercultural communication. The differences derive from the need to adapt the meanings of existing expressions or to find new expressions for different things and to borrow expressions from different cultures. Separation and slow means of com munication also cause differences and encourage one side to retain archaic expres sions that others have abandoned or modified. The differences in vocabulary can be grouped into four categories: the same expression with differences in style, con notation, and/or frequency; the same expression with one or more shared and dif ferent meanings; the same expression with completely different meanings; and dif ferent expressions with the same shared meaning. These differences in vocabularies affect understanding of all varieties of English. To bridge differences in Enghsh language vocabularies, international business communication teachers and trainers must devote more attention to English as the dominant language of international business, create awareness of important vocabulary differences that have the potential to confound intercultural communication, and develop and teach strate gies for bridging the vocabulary differences of English speakers.