Recent advances in understanding and modelling snowcover dynamics are leading to better assessment of snow-atmosphere energy and mass exchange in mountain environments. One particularly important area of advance is in the coupling of complex terrain windflow with solar irradiance, wind transport of snow, sublimation and snowmelt calculations. Results from this show that detailed physically based wind flow calculations are necessary to estimate the spatial patterns of alpine snow accumulation and ablation and that these spatial patterns control the areal depletion of snowcover into summer. A second area of advance is in the measurement, understanding and simulation of snow-vegetation interactions at treelines, in shrub-tundra and in discontinuous forest canopies. This has required a better understanding of canopy radiative, aerodynamic and thermal properties and the complex interactions between the atmosphere, discontinuous plant canopies and underlying or adjacent snowcover. Results from these investigations are showing that simple 1-D representations of plant canopies cannot succeed in providing the radiative and aerodynamic exchanges needed for accurate snow ablation calculations and that fascinating relationships between snow accumulation patterns, solar and thermal irradiance and turbulent transfer develop in sparse canopies and dominate snow dynamics in these environments. The current challenge is to represent these spatial heterogeneities at an appropriate level of complexity in upscaled mass and energy balance calculations for land surface schemes and hydrological models.