doi:10.1016/j.jenvp.2018.12.001engCollado, S.Evans, G.W.Outcome expectancy: A key factor to understanding childhood exposure to nature and children's pro-environmental behaviorART-2019-109717Introduction Human behavior is largely responsible for the environmental issues we face today (Cook et al., 2013), requiring a deeper understanding of the substance and etiology of pro-environmental behaviors (Gifford, 2011; Otto, Kaiser, & Arnold, 2014; Schultz & Kaiser, 2012). Pro-environmental behavior refers to actions that contribute to the sustainability of nature (Schultz & Kaiser, 2012). Given that children will be the ones grappling with future environmental challenges, and that most environmental education programs are organized for youngsters, a better understanding of the factors and processes leading children to behave in a more environmentally responsible manner is relevant both for scientific and practical reasons. One of the most widely documented correlates of pro-environmental behavior is childhood experiences in natural environments (Chawla & Derr, 2012; Cheng & Monroe, 2012; Evans, Otto, & Kaiser, 2018). Several ideas have been offered to explain why experiences in nature at an early age could play a formative role in children's pro-environmental behaviors...2019http://zaguan.unizar.es/record/8628710.1016/j.jenvp.2018.12.001http://zaguan.unizar.es/record/86287oai:zaguan.unizar.es:86287info:eu-repo/grantAgreement/ES/MINECO/PSI-2013-44939JOURNAL OF ENVIRONMENTAL PSYCHOLOGY 61 (2019), 30-36by-nc-ndhttp://creativecommons.org/licenses/by-nc-nd/3.0/es/info:eu-repo/semantics/openAccess