https://doi.org/10.1177/1359105320925150 Journal of Health Psychology 1–13 © The Author(s) 2020 Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/1359105320925150 journals.sagepub.com/home/hpq Abstract Participants with prediabetes were supported to achieve and maintain weight loss with a stage-based behavior change group program named PREview behavior Modification Intervention Toolbox (PREMIT). The tendency to engage in a process of goal adjustment was examined in relation to PREMIT attendance. Analyses were based on 1857 participants who had achieved ⩾8percent weight loss. Tendency to engage in a process of goal adjustment appeared not to be influenced by PREMIT attendance. Instead, results suggested that when unsure about reaching an intervention goal, participants were more likely to engage in a process of goal adjustment, possibly lessening distress due to potentially unachievable goals, either weight loss or maintenance. Keywords behavior change, goal adjustment, lifestyle, prevention, type 2 diabetes mellitus Goal achievement and adaptive goal adjustment in a behavioral intervention for participants with prediabetes Maija Huttunen-Lenz 1 , Sylvia Hansen 2,3 , Pia Siig Vestentoft 4 , Thomas Meinert Larsen 4 , Margriet Westerterp-Plantenga 5 , Mathijs Drummen 5 , Tanja Adam 5 , Ian Macdonald 6 , Moira Taylor 6 , Elizabeth Simpson 6 , J Alfredo Martinez 7,8,9 , Santiago Navas-Carretero 7,8 , Teodora Handjieva-Darlenska 10 , Sally D Poppitt 11 , Martha P Silvestre 11,12 , Mikael Fogelholm 13 , Elli Jalo 13 , Roslyn Muirhead 14 , Shannon Brodie 14 , Jennie Brand-Miller 14 , Anne Raben 4 and Wolfgang Schlicht 2 1 University of Education Schwäbisch Gmünd, Germany 2 University of Stuttgart, Germany 3 University of Cologne, Germany 4 University of Copenhagen, Denmark 5 Maastricht University, The Netherlands 6 University of Nottingham, UK 7 University of Navarra, Spain 8 CIBERonn Instituto de Salud Carlos III, Spain 9 IMDEA Food Institute, Spain 10 Medical University of Sofia, Bulgaria 925150HPQ 0 0 10.1177/1359105320925150Journal of Health PsychologyHuttunen-Lenz et al. research-article 2020 Article 11 The University of Auckland, New Zealand 12 NOVA University of Lisbon, Portugal 13 University of Helsinki, Finland 14 The University of Sydney, Australia Corresponding author: Maija Huttunen-Lenz, Institute of Nursing Science, University of Education Schwäbisch Gmünd, Oberbettringerstr. 200, 73525 Schwäbisch Gmünd, Germany. Email: maija.huttunen-lenz@ph-gmuend.de