The three structural possibilities marking a noun with an English article are "a," "the," and "Ø" (the absence of an article). Although these structural possibilities are simple, they encode a multitude of semantic and pragmatic functions, and it is these complex form-function interactions that this study explores and explains using a semantic map model. The semantic map that is proposed contains three dimensions, which I refer to as Grammatical Number, Referentiality, and Discourse Mode. Each of these dimensions contains a number of further semantic values or pragmatic functions--which I will label "attributes"-that are implicated in English article choice. Various semantic map versions are tested and compared with a methodological approach that uses data collected in a controlled protocol from an elicited conversational discourse. The version that performed best is used as a basis for proposing a comprehensive semantic map that includes the following dimensions and dimensional attributes: a Number dimension with 3 attributes (singular, plural, and uncountable); a Referentiality dimension with 11 attributes, including 7 referential attributes that describe kinds of identifiability (proper names, shared lexis, shared speech situation, frame, current discourse, identifiable to speaker only ["new reference"], and identifiable to neither speaker nor listener [non-specific]) as well as 4 non-referential attributes (categorization, general non-referential expressions, finite verb [verb-object] "noun incorporation," and idioms); and a Discourse Mode dimension with 4 attributes (headline, immediacy, normal, and reintroducing). This model of English articles contributes to the field of research on articles as well as to the field of English language instruction and learning. In addition, it is suggested that the methodological paradigm used to test the semantic map model may be useful as an experimental paradigm for testing semantic maps of other constructions and languages. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]