The wealth of observational data from multiple spacecraft currently in operation at different locations throughout the heliosphere have revolutionized our understanding of 1) the morphology, topology, and evolution of solar and heliospheric structures that adversely impact geospace and other planetary systems; 2) properties of the solar wind and the embedded magnetic field in which these disturbances propagate; 3) the acceleration and transport of solar and heliospheric particle populations, and 4) heliosphere’s boundaries and their interactions with the interstellar neighborhood. To answer these critical questions and make significant progress in the combined areas of outer heliosphere, particle acceleration, and space weather research, the US National Research Council’s 2012 Solar and Space Physics Decadal Survey recommended that NASA implement the Interstellar Mapping and Acceleration Probe (IMAP) mission as the next and highest priority science target for the Solar Terrestrial Probes (STP) mission line. This session solicits relevant theoretical considerations, numerical simulations, and remote and in-situ observational results from multiple vantage points that have led to tremendous breakthroughs that will help develop a complete picture of the structure and pre-conditioning of interplanetary space and how this affects the evolving and propagating disturbances in the inner heliosphere, the acceleration and transport of energetic particles throughout the heliosphere, and how our heliosphere interacts with the local interstellar bubble.