Wave-dominated sandy beaches are highly valued by societies and are amongst the world's most energetic and dynamic environments. On wave-dominated beaches with unlimited sand supply and limited influence of tide and geology, beach change has long been conceptualised in the morphodynamic framework of Wright and Short (1984) . Such framework describes the occurrence of beach types based on wave conditions and sediment characteristics across the complete reflective-dissipative spectrum. Building

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... theoretical work, field/laboratory measurements and monitoring programmes, the physical mechanisms underpinning this morphodynamic framework have been progressively unravelled. Cross-shore morphological changes are primarily controlled by equilibrium and beach memory principles with below (above) average wave conditions driving down-state (up-state) transitions associated with onshore (offshore) sediment transport. Such cross-shore behaviour mostly reflects the imbalance between the onshoredirected sediment transport driven by wave nonlinearities and the offshore-directed sediment transport driven by the undertow. Self-organised morphological instabilities resulting from different positive feedback mechanisms are primarily responsible for alongshore morphological variability and the generation of rhythmic morphological features, such as crescentic bars, rip channels and beach cusps. Critically, wave climate and changes in wave regimes are key in driving the coupled cross-shore and longshore behaviour that ultimately explains modal beach state and frequency-response characteristics of beach morphological time series. Impact statement Sandy beach morphology exhibits a large variability in space and time. Closely associated with such morphological variability are changes in the surf zone processes, such as type of wave breaking, wave energy gradients, strength and character of nearshore currents and modes of sediment transport. The beach model morphodynamic framework of Wright and Short (1984) captures this mutual feedback between morphological and hydrodynamic variabilities, and describes the occurrence of beach types across the complete reflective-dissipative spectrum. In this review, we provide this framework with a stronger physical underpinning by drawing on the results of several decades of coastal research, whilst also highlighting existing gaps in our knowledge and providing future perspectives. This review will provide physical coastal researchers with an enhanced morphodynamic framework within which to place their beach research and interpret their results, as well as providing them with suggestions for future research. However, sandy beaches are not only of interest and of relevance to physical coastal researchers, because beach morphodynamics directly affects, amongst others, beach ecology, pollutant dispersal in the surf zone and beach hazards. Anyone involved with these processes, either from a scientific or management point of view, will benefit from the enhanced beach model morphodynamic framework presented in this review.