Host-pathogen dynamics depends on the interaction between the host, the pathogen and the environment. Amongst environmental factors, temperature strongly impacts the host, the pathogen, and their interaction. In the context of global warming, temperature regimes in freshwater environments are changing, including both gradual increase in the mean water temperature and increase in frequency, duration and magnitude of extreme temperature events, such as heat waves. Biological effects of realistic temperature regimes, like diurnal temperature fluctuations and heat waves, are largely unexplored to date. Thus, we aim to explore the effects of different temperature regimes on host-pathogen dynamics. As a model we will use crayfish plague, a disease of noble crayfish caused by Aphanomyces astaci. To gain an in-depth understanding, we will investigate effects of different temperature regimes on (1) the pathogen, (2) the host and (3) host-pathogen interactions by simultaneously applying and combining different approaches: (i) exploring the mechanisms of pathogen temperature- dependence by investigating the viability/growth and functional gene expression; (ii) exploring the effect of temperature on host alone and host-pathogen interaction by laboratory infection trials at all levels, from disease expression to host immune response. We will synthesize the results by applying two complementary modelling approaches to predict disease dynamics under different temperature regimes: (i) Dynamic Energy Budget (DEB) models to predict the combined effects of temperature and pathogen stress on the host metabolism and growth, and (ii) Species Distribution Models (SDMs) to predict changes in the potential distribution of target species under different temperature scenarios. The feasibility of the project is possible by the solid base of existing preliminary data and the expertise of the established complementary and multidisciplinary team of scientists in Croatia and Switzerland.