English ‘emphatic do’

English ‘emphatic do’ sentences come in two types, with distinct intonational and semantic–pragmatic properties and different grammatical distributions. This paper presents evidence for the distinction and develops an analysis. Emphatic ‘do’ in both types realises affirmative polarity focus. In the Verum Focus (VF) type, ‘do’ may be the sole focus (‘They DO work hard’), and any additional accent is a focus accent (falling tone). The second type, Contrastive Topic (CT) sentences, are defined by the presence of a CT mark on a phrase (subject, verb phrase or object) which is expressed by an accent with a final fall-rise tone. CT sentences give rise to special implicatures not associated with VF sentences; and unlike VF sentences, CT sentences are a declarative main clause phenomenon, being excluded from (most) embedded environments and questions. The different pragmatic properties and the distributional asymmetry both follow in large part from the meaning of the CT marking, whose presence is what sets off the CT type from the VF type of ‘emphatic do’ sentence.