Two studies investigated whether two conventions in the use of adversative conjunctions in English are acquired by native Spanish-speakers who are highly proficient in English. The two conventions are: (1) selection of "but" to introduce foreground information and (2) use of "although" to introduce background information. Subjects in the first study, conducted in Spanish, were 37 monolingual Spanish-speaking graduate students. Subjects in the second study were 42 native Spanish-speaking graduate students in the United States, all highly proficient in English. In each study, subjects completed two tasks. In the first, they were required to choose either "pero/"but" or "anque/although" to unite two propositions in a sentence. In the second, they read a sentence containing two propositions connected by one of these conjunctions and chose a continuation sentence that elaborated on one of the propositions. Results showed that there is a discourse rule of focus for the use of "pero and anque" in Spanish that parallels the English rule. However, as in English, this rule is not followed by all well-educated native Spanish-speakers. It was those Spanish speakers who follow the rule in Spanish that also follow it in English. Contains 21 references. (MSE)