This paper describes and analyses language norms in a storytelling manual published in the Frenchspeaking part of Switzerland. In the manual, storytelling is conceived as a means of persuasion and thus it appears that an appropriate storytelling should lead to believe or to act. What exactly is "appropriateness" in this specific case? In order to examine this issue, this paper addresses three questions: how storytelling is promoted as an efficient communicative technique; which methods are used to propose and support language norms (by showing "what the storyteller should do" and by saying "how he should do so"); and which are the criteria which define an appropriate story (semantic/formal and functional criteria) and an appropriate telling of the story (communicative and linguistic criteria).