In this paper we describe a tool focusing on analysis, planning and design of CBT programs, called STORYIST. It is a tool for authoring conceptual ideas. The output is not a ready-to-run CBT program but a design from which users can get various multi-platform CBT programs. The process of designing a course usually involves different disciplines and people: problem-domain specialists, teachers, software engineers, psychologists, etc. STORYIST allows the co-operative discussion and design of projects. The overall structure of the CBT program can be improved version by version in a well documented way. Among the distinctive features of STORYIST are: learning goal- centered approach for the development of CBT programs; simultaneous definition of the problem domain, the content of the course and elements of course structure; evolutionary development of the detailed course program structure; reusability of design or design components; producing multi-platform-oriented CBT designs. Authoring with STORYIST actually means to achieve a step by step convergence of learning goals, learning content, and program course structure. The process of convergence passes through three conceptual phases: Conceptual Outline, Detailed Concept and Storyboard (Script). Finally, the author gets a detailed graphic description of the behaviour of the prospective CBT program and he can navigate by sequential or direct links through the whole storyboard. He is able to define a set of multimedia-oriented learning materials for embedding in the CBT programs and he can easily create layouts for learners graphical user interface. Graphical and textual representation and documentation of design components lead to increased performance of the whole course production and follow-up courses. Authors will be able to change the content and the structure easily, following their own ideas, needs, preferences, capabilities and experience.