The present paper will focus on the analysis of the different layers and dimensions of the so called Isma'ili "codes of conduct" for the Yemeni da'wa ("mission"). A remarkable example of "code" is al-Risala al-mujaza of the da'i Ahmad b. Ibrahim al-Nisaburi (d. after 386/996). Here a series of advices for the missionaries of the community are provided, expressing the endeavor of formulating abstract principles on government interfaced with the deployment of anecdotes and dicta from the Isma'ili tradition. Furthermore the "codes" exemplify the confluence of various strands of statecraft, setting out the philosophy of the mission (da'wa) and its organisational structure. In other words, the "codes", viewed together and over a connected chronological timeframe, are more than a literary genre. The "codes" testimony the Tayyibi Isma'ili attitude on preserving books by copying the texts. They are important to limit access to true knowledge only to those who had reached the appropriate stage in their learning process. This is why, traces of the tradition cannot be found in single books, but disseminated through anthologies and summae, in order to ensure that only the religiously educated elite had access to the Tayyibi "codes of conduct". My paper will focus on defining the features of the Isma'ili Tayyibi "codes", which make them a textual tradition, with a specific focus on the demands for specific formulas, on the channels of transmission of the "codes" within the community, and on their reception before and after the relocation of the Tayyibi community to Gujarat, India in 1539.