NEED and DARE may function as either modal auxiliaries or main verbs. Both syntactic patterns are fully acceptable in present-day English, although there exists some variation in use of the two patterns between the different regional varieties, as well as between written and spoken language. The present thesis reports the findings of a corpus-based study of the syntactic variation of NEED and DARE in the two major regional varieties of English, American and British English. The focus was made on the distribution of the different patterns (auxiliary, main verb and blend constructions) of NEED and DARE used with the 1st- and 2nd-person pronouns in the BNC and COCA.