This paper claims that (a) electronic commerce could make good use of messages that have semantic complexity considerablely richer than that supported by existing EDI protocols; (b) understanding the logical structure of these semantically complex messages will be materially useful; and (c) the outline of that logical structure has begun to emerge with improved clarity. The focus of the paper is on point (c). The underlying event theory of the semantics of verb phrase modification, which theory has recently appeared in the literature, is especially promising as part of the basis for a formal language for electronic commerce. Not only does this theory supply new and useful representation techniques, but it fits well with prior work on the representation of speech acts.