Geomorphic systems are both complex and complicated; their form, pattern and structure are a result of complex systems behaviour. Complex systems research is a combination of related perspectives and techniques originating from research on nonlinear dynamics and includes concepts of dynamic evolution, fractals, spatial and temporal scales, self-similarity and self-affinity, emergence, self-organisation and self-organised criticality (SOC). Complex system research provides new insights into how geomorphological systems evolve and change. This session should be a platform to discuss critically different concepts related with complex systems research in geomorphology, methods that can be used to understand and identify complex geomorphologic systems as well as two-way coupling between different systems, nonlinear thresholds, emergence, self-organisation and phase transition. Contributions adding applied studies in this context showing advantages and constraints of this perspective in geomorphology are highly welcome.