The authors present a comprehensive overview of past research in ambiguity in the field of psycholinguistics. Experimental results have often been equivocal in allowing a choice between the single-reading hypothesis and the multiple-reading hypothesis of processing of ambiguous sentences. This text reviews the arguments and experimental results in support of each of these views, and further investigates the contributions of context and thematic constraints in the process of ambiguity resolution. Commentary is also made on the possible hierarchical ordering of difficulty in the treatment of ambiguity, as well as critically related considerations like bias, individual differences, general cognitive strategies for dealing with multiphase representations, and the inherent differences between lexical and syntactic ambiguity.