From the late twelfth and early thirteenth century onwards, against the backdrop of demographic growth and urbanization, a growing number of laypeople started to pursue a religious life without actually joining the clergy. They had not professed and did not follow a traditional monastic rule. Instead they adhered to ascetic and penitential ideals in which meditation and prayer, charity, methodical work, as well as the reading of vernacular spiritual texts played a central role. Among these semireligious” people were beguines, beghards, Tertiaries, Brothers and Sisters of the Common Life as well as some sporadic movements like for example flagellants. In this project I will study the ascetic and penitential spirituality in semi-religious groups of the late medieval Low Countries. Initially, I will carry out an analysis of the spiritual literacy in semi-religious communities, based on extant manuscripts, reading lists, library catalogues, etc. A second set of research questions examines the way in which the ascetic and penitential culture of different types of semi-religious movements was implemented in their daily practices, their work ethics, their rituals of confession and penance, etc. Finally, in a third research phase, I will analyse how the ascetic and penitential culture required a thorough conditioning of the inner life and the emotional behaviour of those belonging to semi-religious communities.