Research topic/aim: School knowledge versus everyday knowledge is a fundamental issue in education. The research project Adults’ mathematics: In work and for school seeks to reverse the one-way assumption from school to workplace knowledge and to learn from workplace activity what might be appropriate for vocational education and training. The objective is to analyze and understand adults’ mathematics-containing work competences – including social and affective aspects – complementing studies of mathematical qualifications in formal vocational education. Theoretical framework: The so-called “transfer” of mathematics between school and workplace – and vice versa – is not straightforward (Hoyles et al. 2001, Wedege, 1999). Moreover, the distribution of knowledge in society defines the distribution of power and – in this context – people’s everyday competences do not count as mathematics (FitzSimons, 2002, Valero & Wedege, 2009). One of the reasons is that mathematics is integrated within workplace activities and often hidden in technology: Mathematical elements are subsumed into routines, structured by mediating artefacts (e.g., texts, tools) and integrated in workers’ competences. Another is that adults do not recognize what they do at work as mathematics, which they identify with algorithmic task solving (Wedege, 1999). Methodology/research design: The problem complex will be studied through empirical investigations – quantitative (survey) and qualitative (observations and interviews) – in interplay with theoretical constructions. This paper discusses methodological issues related to reversing the one-way assumption from school knowledge to workplace knowledge and to learn from workplace activity what might be appropriate for adult vocational education. Expected conclusions/findings: It is argued that any methodology for researching the dynamics of workers’ mathematics in work and for school has to combine a general approach – starting with demands from the labour market and school mathematics – and a subjective approach starting with the individual’s needs and competences in work. In Salling Olesen (2008) we find a working model for researching the dynamics of workplace learning in general which includes and combines these two approaches. “It mediates the specific relation between (…): the societal work process, the knowledge available and subjective experiences of the worker(s)” (p.118). Relevance for Nordic Educational research: In the Nordic countries, lifelong learning – as a discourse of education – assumes that learning takes place in all spheres of life. Thus, the issue presented above is highly relevant and the work is also based on Danish, Finnish and Swedish research in adult and vocational education.