Dear colleagues, As a co-organizer of the session /Building Data Collection Methods for Hard to Study Populations/ at the 5th ISA Forum of Sociology (https://www.isa-sociology.org/en/conferences/forum/rabat-2025 ) I would like to bring this session to your attention: This session focusses on research that explores, develops or tests structured data collection methods that are suitable for hard to study populations. These are populations like low literate people, people with cognitive limitations, (mental) health challenges, or subgroups with physical restraints like in hearing or speaking. They all have in common to be at greater risk of communicative, cognitive and/or motivational disabilities that may limit the application of standardized or structured data collection methods. As a result, these limitations may pose a threat to (survey) research validity and reliability. If alternative, appropriate methods are not developed and applied, such populations and subgroups continue to be under researched and data quality will remain hampered While in the end the aim may be to create new methodology for structured or even standardized (survey) research, the focus of papers can be on theoretical, qualitative, quantitative, or mixed methods developments. In this session, we welcome theoretical and empirical contributions on issues that are key to data collection in hard to study populations, like: • Cognitive and communicative processes. • Verbal and non-verbal behaviour. • Sensitive topics and emotional burden. • Power differences in research. • Interactive aspects of data collection. • Proxy and triad interviewing. • Visual data collection methods. • Aided recall measures. • Timeline and Life History Calendar tools. • Development of tools and instruments. Hence this session invites papers dealing with innovative data collection approaches that seek to meet the challenges in collecting structured data from special populations.   I would like to invite you all to have a look. We are looking forward to receiving your contributions BEFORE THE 15TH OF OCTOBER. More information can be found here: https://isaconf.confex.com/isaconf/forum2025/webprogrampreliminary/Session21... With kind regards, VANESSA TORRES VAN GRINSVEN | Assistant Professor Faculty of Psychology | Section Theory, Methods and Statistics Visiting address: Valkenburgerweg 177 Heerlen Postal address: Postbus 2960 6401 DL Heerlen vanessa.torresvangrinsven@ou.nl  [1] Wissenschaftliche Mitarbeiterin Universität zu Köln Humanwissenschaftliche Fakultät Department Heilpädagogik und Rehabilitation Arbeitsbereich Forschungsmethoden Postanschrift: Frangenheimstraße 4 in 50931 Köln Hausanschrift: Aachener Straße 197-199 in 50933 Köln Tel: + 49 221 470 7409 E-Mail: v.torresvangrinsven@uni-koeln.de[1] Homepage: Beratungsstelle für Empirische Forschung[2] Links: ------ [1] [2] https://www.hf.uni-koeln.de/39424?lang=2