Much of the controversy surrounding the autonomy of syntax issue has focused on whether prepositional phrase (PP) attachments can be influenced by prira- discourse context. W e briefly review four studies that have produced results supporting either the autonomy view or the interactive view, and then describe the results of a recent series of experiments that identify the conditions under which a read^ will be garden pathed when encountering a structurally ambiguous PP. The results of these experiments suggest that a reader can avoid being led down the garden path by a discourse that successfully creates referential ambiguity, but only in sentences where the verb does not require the P P in order to be grammatical. W e also describe a restricted interactive parser that can account for these empirical results. The parser divides its task between two processors that use limited forms of semantic and discourse information when making attachments.