Particle and meshfree methods have emerged as powerful computational frameworks for simulating complex physical phenomena involving large deformations, moving interfaces, and evolving topologies. Despite their success, achieving high-order accuracy, numerical consistency, and long-term stability remains a significant challenge. This session provides a multidisciplinary forum for presenting recent advances in theoretical foundations, numerical formulations, and algorithmic developments, including hybrid data-driven computational frameworks, for particle and meshfree methods. Particular emphasis will be placed on high-order spatial discretization, advanced time-integration techniques, and efficient algorithms for incompressible, multiphase, and multiphysics systems. Topics of interest include consistent boundary treatments, particle regularization and shifting techniques, adaptive and multi-resolution approaches, error estimation, and coupled problems such as fluid–structure interaction. Contributions addressing both fundamental methodological developments and challenging engineering applications are highly encouraged.