A central problem for successful evidential uses of measurement has recently been addressed by noticing how the answers to the questions, “What counts as a measurement of X?” and “What is X?” often seem to presuppose one another, particularly when a theoretical understanding of the quantity of interest is weak (cf. van Fraassen 2008). In continuity with a similar concern raised in the early days of philosophy of science (Mach 1896, Reichenbach 1920; cf. Padovani 2015), recent literature in philosophy of measurement has discussed this circularity risk as the problem of coordination (e.g., van Fraassen 2008, McClimans 2013, Luchetti 2020, Ohnesorge 2022, Tal 2013) or the problem of nomic measurement (e.g., Chang 2004, Cartwright and Bradburn 2011). This problem, although cashed out in slightly different forms, has also been central to discussions of validity – particularly of measurement and construct validity – in psychometrics, education, and other human and health sciences (e.g., Cronbach and Meehl 1955, Borsboom 2005, Alexandrova and Haybron 2016, Alexandrova 2017, Feest 2020, Larroulet Philippi 2020). While virtually dealing with the same problem, these two branches of the literature have scarcely interacted with each other from a philosophical and methodological point of view. This workshop will bring together philosophers working in the HPS tradition that have dealt with either or both the problem of coordination and measurement/construct validity in science and medicine to address, among others, the following questions: Do coordination and measurement/construct validity concern the very same problem? If so, what disciplinary specificities have determined the emergence of two different labels and philosophicalmethodological discussions? How can these two inform one another, particularly to advance our understanding of validity in the human and health sciences? Can the tradition discussing coordination, more concerned with the physical sciences, provide relevant input for addressing issues of measurement/construct validity in, e.g., psychometrics? If not, why is that so?