This is undeniably the most comprehensive English-Irish dictionary available. It was originally published by the Irish government in 1959 and is often used as a companion to the O Donaill Irish-English dictionary. The preface is in English. The thing I like best about this book is the larger number of examples of usage that are included in the entries. The book translates common English phrases into Irish, which is very helpful to the learner. For example, under the entry for the English verb *grind*, there are seventeen lines of explanation, with translations for several short English phrases, such as *to grind ones teeth*, *to grind an organ*, *to grind for an exam* etc. Altogether an invaluable book for anybody who wants to write coherently in the Irish language.