This paper attempts to discuss and describe the research on four specific areas which, in the author's opinion, are not fully understood in spite of their great significance to the training and actual work of translators and which, therefore, should constitute an integral part of any general bilingual dictionary designed for translators. These are collocation, style, synonymy and certain grammatical features. Such examination is deemed imperative for two reasons. First, dictionaries of all kinds have been compiled for an extremely wide variety of users. One of the groups that has been overlooked, however, is the professional translator. No other gorup, professional or otherwise, utilises dictionaries at all levels as extensively as this group. Second, the impact these areas have on the quality of the work produced has never been thoroughly investigated from a translator's point of view. The major language of illustration in this article is English and the issues are reviewed from an Arab translator's point of view.