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A proper understanding of the transport of energetic charged particles in space plasmas, whether heliospheric or in other, broader, astrophysical contexts, requires insight into how such particles are affected by plasma turbulence. This is especially necessary in heliospheric scenarios, where accurate, and above all realistic, numerical particle transport models can play a significant role in the mitigation of the harmful effects of these particles on human endeavours in space. In the past, much insight has been gained from direct simulations of test particle interactions with synthetic turbulent magnetic fluctuations, particularly in terms of particle diffusion and drift coefficients. For most models, however, the synthetic turbulence did not reproduce many of the features of magnetic turbulence observed in the solar wind. This proposal aims to bring together experts in various fields, broadly centered on the study of plasma turbulence and comprised of specialists in theory, data analysis, and charged particle transport modeling. This will take advantage not only of recent advances in our understanding of space plasma turbulence due to careful analyses of in-situ spacecraft observations in the inner heliosphere (such as those performed by Parker Solar Probe and Solar Orbiter), but also of the latest developments in the numerical simulation of turbulence over multiple orders of magnitude in length scales. Simulations and data analyses pursued by the team serve as inputs for the next generation of numerical test-particle models. This includes the effects of coherent features such as current sheets and flux ropes in the turbulence, which in turn will enable novel insights into how particle transport and acceleration is modified with regard to effective diffusion coefficients and non-diffusive propagation regimes. The results will be incorporated into existing particle transport models for heliospheric and astrophysical scenarios, with direct predictions for radiation signatures and validation with in-situ spacecraft particle observations.