Students from six countries--Australia, Japan, Mexico, Sweden, Taiwan, and the United States--recalled the extent to which their best or worst professors used various forms of communication that have been associated with effective teaching. Across cultures, best professors were perceived to employ more nonverbal expressiveness, relaxed movement, in-class conversation, and out-of-class communication than worst professors. Relative to Japanese and Taiwanese students, Australian and U.S. students perceived their professors to use more nonverbal expressiveness. Students from Australia, Sweden, and the U.S. also perceived their best professors to use more in-class conversation than students from Japan or Taiwan perceived their best professors to use. However, Australian and U.S. students also perceived their best professors to use "less" out-of-class communication than did students from the other four countries. There were also differences in the forms of communication that discriminated between best and worst professors in each culture. For example, nonverbal expressiveness and in-class conversation were the best discriminators for Australian and U.S. students, whereas out-of-class communication and relaxed movement were the best discriminators for Japanese and Taiwanese students.