Using 61 acronyms and initialisms culled from Web sites in May 2003, this study shows that the syntactic behavior of abbreviations from phrases is regular. When a definite description is abbreviated, its syntactic category is predictable, depending on whether the result is an acronym (ERIC, NAFTA) or an initialism (FBI, NSF). Acronyms behave like proper names and drop the definite determiner: “ERIC produces a variety of publications….” Initialisms continue to behave like common compound nouns and retain the determiner: “… the FBI has unique response capabilities….” Two frequent exceptions, university names (UCLA) and television networks (NBC), are shown to act like bare locative nominals in English (go to school). Other apparent exceptions (GE, AA) are also shown to exhibit regularity.