This paper offers a phase-based analysis of adverb licensing, focusing on speech-act adverbs and epistemic adverbs in English, within the minimalist framework developed by Chomsky (2000, 2001, 2005, 2007). Although recent studies have tried to explain the remarkable properties of adverbs with regard to their distribution in terms of licensing, existing approaches such as the specifier-based analysis of Cinque (1999) and the scope-based analysis of Ernst (2002) are problematic. As an alternative, I propose a phase-based analysis of adverb licensing. Specifically, I argue that adverbs are locally c-commanded by their licensers to be properly licensed; and furthermore, that adverbs cannot be licensed by their licensers beyond phases. I show how, based on these arguments, the phase vP affects the distribution of both speech-act adverbs and epistemic adverbs in declarative sentences, and the phase CP plays a crucial role for the distribution of the adverbs in interrogatives. I also consider word order in adverb usage in light of the proposed analysis.