Although successful reading comprehension is described as the interaction of text-based processes and processes related to the reader's existing background knowledge or schemata, under different conditions readers show different patterns of text-based versus knowledge-based processing. Recent research suggests that students of English as a second language (ESL) rely on one or the other process for comprehension, excluding the other. One explanation touches on schema availability, schema activation, skill deficiencies, conceptions about reading in a second language, and individual differences in cognitive style. Research supports the idea that the absence of the content and formal schemata appropriate to a particular text can cause processing difficulties. When schema are available, the text may not contain enough lexical cues to activate them. A unidirectional reading style (text-biased or knowledge-biased) may also be brought out by two opposing skill deficiencies, of linguistic and reading skills. Students may also misunderstand the purpose of ESL reading and the processes expected of them, perhaps as a result of overemphasis on the decoding process, reading passages that are not relevant to readers' interests, and tests stressing literal content. Further research is also recommended on differences in ESL reading comprehension styles similar to other manifestations of cognitive style. (MSE)