Mathematical morphology is a theory for the analysis and processing of geometrical structures that provides highly efficient tools for numerous signal and image processing tasks with a wide range of applications. Designed originally for binary and grey-value data, morphological operations have been generalised to process multi-channel and even matrix-valued data on regular grids as well as graphs. Traditional algebraic lattice approaches have been complemented by PDE concepts. The minisymposium will bring together scientists involved in these thriving developments to share ideas, discuss connections, and promote a deeper understanding of the common principles behind different approaches to morphological image processing.