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The small-scale physics within the first centimeters above the wavy air–sea interface are the gateway for momentum and scalar fluxes between the atmosphere and the ocean. The wind transfers momentum and energy into surface currents and waves, which in turn significantly modulate the structure of the wind stress, through complex feedback mechanisms. In spite of extensive work on the topic, the details of wind-wave momentum exchanges remain unclear, and specifically the partitioning of wind stress, between viscous, pressure, and turbulent contributions. This is due, in part, to the technical challenges involved in measuring small-scale dynamics within the highly dynamic, coupled air-water wave boundary layers. Using a unique wind/wave measurement system, combining particle image velocimetry and laser-induced fluorescence techniques, we were able to resolve small-scale airflow dynamics within the first tens of microns to centimeters above wind-waves, in the laboratory and the field. Separated and non-separated sheltering events were directly observed and quantified over young, strongly forced wind-waves; we attempt to connect these events with relevant wind-wave parameters, such as wave age and slope. In spite of significant modulations of the surface viscous stress along the waves, especially in the presence of intense sheltering events, our results suggest a very limited contribution of viscous stress to wind-wave growth.