In American Sign Language (ASL), conjunction (‘and’) and disjunction (‘or’) are often conveyed by the same general use coordinator (transcribed as “COORD”). So the sequence of signs MARY WANT TEA COORD COFFEE can be interpreted as ‘Mary wants tea or coffee’ or ‘Mary wants tea and coffee’ depending on contextual, prosodic, or other lexical cues. This paper takes the first steps in describing the syntax and semantics of two general use coordinators in ASL, finding that they have a similar syntactic distribution to English coordinators and and or. Semantically, arguments are made against an ambiguity approach to account for the conjunctive and disjunctive readings; instead, I propose a Hamblin-style alternative semantics where the disjunctive and conjunctive force comes from external quantification over a set of alternatives. The pragmatic consequences of using only a prosodic distinction between disjunction from conjunction is examined via a felicity judgement study of scalar implicatures. Results indicate decreased scalar implicatures when COORD is used as disjunction, supporting the semantic analysis and suggesting that the contrast of lexical items in the scale plays an important role in its pragmatics. Extensions to other languages with potential general use coordination are discussed.http://dx.doi.org/10.3765/sp.6.4