In this issue of Medical Writing dedicated to regulatory writing, many of the articles provide some glimpses of the day-to-day problems and dilemmas faced by regulatory writers. It is hard, however, to describe the essence of regulatory writing in a succinct and comprehensive fashion. For my column in this issue, I have provided a glossary (by no means exhaustive) of some of the more common terms used by regulatory writers, with an description of what they mean in the context of day-to-day working life. My hope is that through describing the way jargon is used by regulatory writers, I can transmit a feel for the less intangible aspects of the job.