Clinically oriented interface terminologies support interactions between humans and computer programs that accept structured entry of healthcare information. This manuscript describes efforts over the past decade to introduce an interface terminology called CHISL (Categorical Health Information Structured Lexicon) into clinical practice as part of a computer-based documentation application at Vanderbilt University Medical Center. Vanderbilt supports a spectrum of electronic documentation modalities, ranging from transcribed dictation, to a partial template of free-form notes, to strict, structured data capture. Vanderbilt encourages clinicians to use what they perceive as the most appropriate form of clinical note entry for each given clinical situation. In this setting, CHISL occupies an important niche in clinical documentation. This manuscript reports challenges developers faced in deploying CHISL, and discusses observations about its usage, but does not review other relevant work in the field.