Instructional text, and procedural text in particular, is a genre that users heavily rely upon when they are learning new procedures, devices or systems. It is, however, also well-known to be a genre that is difficult to produce and maintain. This article discusses Isolde2, an environment that attempts to address this problem by supporting the semi-automated production of procedural instructions, online help in particular. This environment exploits technologies for producing documents automatically and includes an extensible set of interactive tools for acquiring, representing, and maintaining the knowledge that is required for producing the instructions. In addition, this article presents the results of an evaluation that compares the effectiveness of the instructions produced by Isolde with those produced by human authors. The results suggest that the instructions produced by Isolde are of comparable quality to similar texts found in commercial manuals.