Cosmic rays provide an important probe of particle acceleration and transport processes throughout the heliosphere. They include solar energetic particles (SEPs), accelerated during solar eruptive events, and galactic cosmic rays (GCRs), which originate outside the heliosphere and are modulated by heliospheric conditions. Their variability reflects the complex interplay between energetic particles and solar and heliospheric activity across a wide range of spatial and temporal scales. This session will focus on the acceleration, transport, modulation, and variability of cosmic rays in the heliosphere, including, but not limited to, SEPs, Forbush decreases, anisotropic cosmic ray enhancements (ACREs), and longer-term variations in GCR fluxes. We invite contributions addressing observations, modelling, data analysis, and the phenomenology of cosmic rays in the heliosphere, as well as their connections to solar and heliospheric dynamics. We particularly encourage contributions that employ or combine multi-spacecraft and ground-based observations, numerical and theoretical models, novel data-analysis techniques, and forecasting approaches, as well as studies that connect measurements across different spatial and temporal scales and regions of the heliosphere.