What My project will investigate the effectiveness of prospective self-control strategies and their potential for improving people's self-control. Prospective self-control strategies seek to prevent the emergence or limit the strength of temptations, thereby reducing the need for the effortful self-control, which generally has a rather modest success rate. In doing so, I will specifically focus on two prospective self-control strategies: situation selection and goal support. Situation selection involves strategically identifying and avoiding tempting situations (e.g., a smoker avoiding bars that allow smoking), whereas goal support involves pursuing goals in the company of other people who actively support these goals (e.g., an aspiring runner running together with a running 'buddy'). Why Extensive research has identified self-control as an important predictor of leading a healthy, financially stable, and happy life. Self-control is also a significant predictor of the success of people's behavior change efforts. Yet, the precise mechanisms through which self-control leads to successful behavior change and life outcomes are still not well understood. This also means that our current knowledge of how to improve people's self-control is limited. Recent research has identified numerous self-control strategies used by people who are generally good at self-control. However, research on the effectiveness of individual self-control strategies is still in its infancy and further evidence is needed to properly evaluate their merits. How My project involves a two-part research program. First, I will investigate people's meta-knowledge of the scope of self-control strategies, what self-control strategies they commonly use, and whether they deliberately select between them based on their perceived effectiveness. This will be done through an online survey with a nationally representative sample. Second, I will investigate the effectiveness of two prospective self-control strategies (situation selection and goal support) in ensuring progress on important personal goals. I plan to examine this through an online randomized controlled trial with an experience-sampling design, which permits obtaining causal and longitudinal estimates of the strategies' effectiveness with limited intrusion from memory biases. SSR Self-control is a critical component of behavior change, which is currently center-stage in societal efforts to mitigate climate change, reverse global biodiversity loss, combat the COVID-19 pandemic, and improve public health more broadly. Self-control is also positively linked to physical and mental health (e.g., lower stress and anxiety), subjective wellbeing, personal financial stability, educational achievement, and relationship quality. Thus, identifying effectiveness interventions for improving people's self-control may have considerable personal and societal benefits.