Abstract.  This paper takes the treatment of antonymy in Collins COBUILD Advanced Learner’s English Dictionary (2003) as the point of departure for a discussion about the principles of antonym inclusion in dictionaries and corpus methodologies in lexicology. Ccaled includes canonical antonyms such as good/bad and dead/alive, as well as more contextually restricted pairings such as hot/mild and flat/fizzy. The vast majority of the antonymic pairings in the dictionary are adjectives. Most of the antonyms are morphologically different from the headwords they define and typically do not involve antonymic affixes such as non–, un– or –less. Only just over one-third of the total number of pairs is given in both directions. The principles for when antonyms are included in ccaled are not transparent. We propose an initial top-down corpus-driven method to support decisions about antonym selection and inclusion.