The goal of this research is to form the basis of future interventions aimed at stimulating pro-environmental behavior for the Netherlands and Germany. Study 1 entails a network analysis aimed at identifying which of multiple cognitive, affective, and behavioral constructs is central (i.e., most influential to all other constructs, including pro-environmental behavior). In Study 2, the central constructs found in Study 1 are experimentally manipulated to examine their causal effect on pro-environmental behavior. This set-up is based on research by Zwicker et al. (2020), who identified climate change guilt as a central construct and studied its effects on sustainable consumer behaviour in 18- through 70-year-old Westerners using a similar methodology. Novel is the focus on a more narrow age range (i.e., 18- through 24-year-olds). This is relevant because of the rising notion that a one-size-fits-all approach to stimulating pro-environmental behavior is overly simplistic and the reason for many seemingly paradoxical reports of effectiveness (Chapman, Lickel, & Markowitz, 2017). As several climate change-related attitudes and emotions have been found to differ between age groups (Corner et al., 2015; Kuthe et al., 2019; Ojala, 2012; Reinhard, 2018), it may thus be prudent to focus on a specific age group when devising an intervention. We focus on the young end of the age spectrum as younger individuals tend to be more receptive to climate change information (Stevenson et al., 2014), and are more likely to stimulate climate change action in family and peers (Hiramatsu et al., 2014). We focus specifically on young adults as younger age groups may yet lack the autonomy to engage in many relevant behaviors (for example, how much say does a child or teenager have in the products they consume or their methods of transport?). As the Netherlands and Germany - two adjacent, Northern-European democracies - are relatively similar in terms of two of the more prominent demographic predictors of climate change perceptions and ideology, namely political adherence (McCright, Dunlap, & Marquart-Pyatt, 2016; McCright et al., 2016) and national wealth (Lo & Chow, 2015; Sandvik, 2008), only small differences between the climate change networks of these countries may be expected. However, in keeping with the aforementioned notion that one intervention may not be equally effective for all people, we allow for different central constructs (i.e, different focuses for interventions) per country of residence. If the same intervention proves most effective in both countries, this attests to its wide applicability. Differences herein, however, would signal the importance of distinct approaches even for similar countries. Exploratory analyses may then offer insights into possible demographics relevant to these differences. The complete design of the studies, the materials and analyses as well as expectations can be found in the folder "Materials". We present the results of a pilot study with young adults (16- to 24-year-olds) living in the Netherlands (N = 434) in the folder "Pilot Study".