The MRCmachine-usable dictionary contains 150,837 words and up 26 linguistic and psycholin- guistic attributes for each. The attributes are from sources that are publicly available but are difficult to obtain and structure into a single dictionary, Three utility programs are described that permit the selection of words defined by a set of specified attribute values and the selection of attribute values for a set of specified words. These programs permit the construction of word sets for psycholinguistic experiments that control for the attributes specified in the dictionary. The dictionary may also be of use to researchers in artificial intelligence and computer science who require psychological and linguistic descriptions of words.