General Aims of the Project In March 2020, the World Health Organization (WHO, 2020) and the US Centers for Disease Control and Prevention (CDC, 2020) issued advice on preventing the further spread of COVID-19, with handwashing hygiene being the key preventive behavior, to be applied by the general population. Even before the WHO and CDC guidelines were issued, people started to change infection-protective health behaviors. Handwashing change is probably the most prominent, with up to 44% of the general population declaring a behavioral shift (Abacus Data Bulletin, survey conducted from March 3 to 6, 2020). In comparison, 38% made a change referring to coughing into an elbow and 6% increased wearing face masks (Abacus Data Bulletin, 2020). Although behavior change has already occurred and its scale has been investigated, several burning issues remain and require investigation: 1. What are the levels of adherence to handwashing guidelines, across the periods varying in COVID-19 morbidity and mortality, and across countries (k > 10) with different COVID-19 trajectories? 2. Are anxiety and cognitive determinants, derived from the protection motivation model (perceived risk, perceived effectiveness of handwashing) and handwashing behavior associated, with country-levels of COVID-19 morbidity/mortality rates acting as (i) the moderator of these associations, and (ii) the direct predictor of the level of the handwashing adherence? 3. A reduction of handwashing adherence may occur as COVID-19 morbidity/mortality rates decline (Bi et al., 2019). Do modifiable cognitive predictors included in the HAPA model (risk perception, outcome expectancy, self-efficacy, intention, planning, action control) predict further maintenance of handwashing behaviors? Are the associations between these modifiable cognitions and behavior moderated by the trajectory of COVID-19 morbidity and mortality rates Handwashing is the key preventive evidence-based behaviour, limiting the likelihood of the transmission of SARS-Cov-2 (WHO, 2020) in general population. Adoption and maintenance of adherence of handwashing guidelines is limited in general population and the interventions to improve adherence in general population have small effects (Lawson & Vaganay-Miller, 2019). A shift in an approach to explaining handwashing behavior changes is needed to pave the way to new, more effective interventions. COVID-19 epidemic acts as a trigger increasing adherence to handwashing (Wise et al., 2020), but behavior change is likely to be short-lived and a speedy return to old habits may be expected (Bi et al., 2019), increasing the likelihood of an infection. This project will test the complex emotional and cognitive drivers of the changes in handwashing behaviors.