Ambiguous sentences that contain more than one quantified expression present challenges to linguistic theories of quantification and to psycholinguistic theories of real-time sentence comprehension. Based on the results of a set of experiments investigating the comprehension of doubly-quantified sentences and sentences that contain ellipsis, this book argues that the interpretation of quantified sentences is determined at Logical Form (LF), that LF is a syntactic level of re presentation not constrained by semantics, and that LF representations are crucial to interpretive decisions made by the human sentence processing mechanism. The book will be of interest to linguists, psycholinguists, and anyone who studies quantification, the syntax-semantics interface and the role of abstract linguistic structure in sentence comprehension.