specifically devoted to phraseological pitfalls of this kind even though some dictionaries of id- ioms would provide random cross-references warning of idiomatic expressions whose form may mislead the user into thinking that they are semantically related. At the same time, there exist numerous dictionaries of usage bringing to the attention of the learner the difference in the meaning, spelling, pronunciation, and the range of application of individual words characterized by outward similarity.* The present dictionary, providing systematic contrastive coverage of all kinds of phraseological “false friends” and “en- emies,” is expected therefore to remedy this im- balance and to fill, at least partially, the existing lexicographical lacuna. Primarily intended for EFL/ESL students as a tool of reference and pro- phylactics, it presents a complete and orderly catalog of multi-word units that require special consideration because of their interferential po- tential. Furthermore, the sizeable volume of the dictionary and its user-friendly Phrase Index en- able it to be used as a regular phraseological dic- tionary providing definitions to individual id- ioms, clichés and set expressions. In the selection of phrases making up the dictionary I proceeded from the broadest possi- ble concept of phraseology and considered both idiomatic and non-idiomatic recurrent word combinations, prepositional collocations and phrasal verbs. No limits have been set with re- spect to their structural or pragmatic characteris- tics, the principal criteria being similarity or con- trast in the wording or imagery of multi-word units whose meanings or usage do not show cor- responding similarity or contrast. Potentially in- terferential units were culled from the phraseo- logical pool provided by over a hundred mono- and bilingual dictionaries as well as numerous online databases. Contrastive-differentiating analysis of the totality of phraseological units thus selected made it possible to separate groups of semantically and pragmatically similar phrase- ological synonyms and variants (cf.: add fuel to the fire / add fuel to the flames) from interfer- entially significant “false friends.” This inductive methodology made it possible to concentrate not on the actual interferential interactions of phraseological units (error analysis) but on the hypothetical possibility of their confusion, pre- dicting all likely cases of flawed reasoning at phraseological level. As a result, some entries may contain well-known modern phrases whose interferentially relevant oppositions are repre- sented by expressions pertaining to professional or social jargon, slang, as well as by phrases that are regional, dialectal, extinct or rarely heard nowadays. Phraseological oppositions of this sort, though less topical for language learners, demonstrate interesting cases of coincidence in imagery through time and space. Parallel to potentially confusable phraseo- logical oppositions, there are numerous instances when units longer than the word form similar, semantically contrastive relationships with con- sonant compound words, cf.: day-man / man of the day. In many cases dictionaries differ whether to treat a particular two-word combination as a phrase or a compound and there seems to be no hard and fast rule about which category such an item should be in. The distinction between sep- arate and solid writing of such units becomes relevant, however, when it serves to differentiate between semantically dissimilar entities, cf.: back drop / backdrop, or units functioning as different parts of speech, cf.: common sense / commonsense. Since their outward similarity may likewise con- fuse the learner, we deemed it necessary to in- corporate all cases involving potentially inter- ferential compounds in the present dictionary. The dictionary compiled on the above principles is comprehensive in that it encom- passes the whole spectrum of phraseological units irrespective of their contemporary status in the language, social currency, or the degree of idiomaticity (that is, semantic interdepend- ence of their components), the units ranging all the way from free word combinations to id- Introduction 4– *See, for example: G. A. Owen, Dictionary of “Confusibles” (Somerset: Brodie, 1966); A. Room, Room’s Dictionary of Confusibles (London: Routledge & Kegan Paul, 1979); L. Urdang, The Dictionary of Confusable Words (New York: Facts on File, 1988).