When exploring the conceptualisation of inclusion and exclusion, work and profession are a crucial issue to be tackled. The fact that socio-political inclusion and citizenship itself, both in theory and in practice, are closely linked to professional activity has been a key feature of Western society since the early Modern age. According to Weber’s interpretation, the Protestant elaboration of the Beruf – i.e. the calling (vocatio) inherent in the practice of a worldly activity of an economic nature – is fundamental to the modern significance of the profession. However, the Latin roots of the professio have also contributed to the emergence of a notion of the profession as having ethical, political, legal and economic value – and to the emergence of the link between “profession” and “inclusion” in particular. The long-term, synthetic account given in this paper is intended to reveal in terms of “inclusion within an order” the complex interweaving of the theological, political and economic roots of the concept of “profession”. The Roman law institution of the census (professio census), and its subsequent reinterpretations in both theology and law, were key in this process, as some examples will show. The act of declaration made in front of Roman censors implies admission within a political, military and fiscal order: the holding of citizenship was contingent upon this act. This institution was introduced into Christian thought (e.g. Origen, Ambrose) by the exegesis of the census carried out at the time of Jesus’s birth (Luke, 2, 1-5), and took on a redemptive meaning: the declaration of faith (professio fidei) was understood as a census of souls necessary for the heavenly citizenry, and the professio thus became an act of inclusion and salvific submission to God and his order. This interpretative tradition helps to explain the medieval conceptualisation of the religious profession, i.e. the act sanctioning the joining of a religious order, which, from Isidore of Seville onwards, was called professio monachi and reproduced the joining of a military order. Reference to the professio census was also used – as is confirmed by the use that Dante Alighieri and some medieval jurists made of Luke’s pericope – to legitimise the Christian submission to political authority. In all these cases, the professio echoes the Roman juridical institution and coincides with the act of inclusion within an established - social, theological and/or political - order. From Ancient Rome to the Middle Ages, the profession (and thus the order to which it guarantees access) assumes a dual politico-legal and theological, rather more than economic, dimension. However, during the slow process of the valorisation and moralisation of the vita activa which characterizes the last centuries of the Middle Ages, it is the economic dimension that gains importance. The nature of this order then undergoes radical changes, at the end of which the profession will have taken a sharp turn towards its contemporary incarnation, in which it coincides with full participation in the order of a regulated economic life – a participation that is essential to the socio-political inclusion.