This thematic issue adresses the knowledge, skills and values in welfare-to-work programmes (WtW) with disadvantaged clients. The aim of this special issue is to explore the status and development of professional work in WtW settings. In most countries, front-line workers implementing activation measures have no clear professional profile, and are recruited from a variety of professions, making them a heterogeneous group (Caswell et al. 2017). Scholars disagree on whether this area should be understood as de-professionalized administrative work, an emerging professional field of 'activation work', or a new specialization within social work (Andreassen and Natland 2022; Nothdurfter 2016; Nothdurfter and Olesen 2017; Raeymaeckers and Dierckx 2013; van Berkel, Penning de Vries, and van der Aa 2022). These questions are important because the way frontline workers manage the tensions between institutional policies and professional values in their everyday work is crucial for the welfare of vulnerable clients, and several studies have pointed to the importance of frontline workers' orientations in the implementation of welfare policy (e.g. Gjersoe, Leseth, and Vilhena 2020; Jessen and Tufte 2014). Nevertheless, few studies have examined what forms of knowledge, skills and values are present and how they are shaped in the everyday work at the front lines of WtW.