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The BIOPHYS algorithm provides innovative and flexible methods for the inversion of canopy reflectance models (CRM) to derive essential biophysical structural information (BSI) for monitoring, inventory and quantifying vegetation state and disturbance, and for input to ecosystem, climate and carbon models [1-9]. Based on spectral, angular, temporal and scene geometry inputs that can be provided or automatically derived, the BIOPHYS Multiple-Forward Mode (MFM) approach generates look-up tables (LUTs) that comprise reflectance data, structural inputs over specified or computed ranges, and the associated CRM output from forward mode runs. Image pixel and model LUT spectral values are then matched and retrieved, with the corresponding BSI associated with the matches output as the vegetation BSI results. BIOPHYS-MFM has been extensively used and validated over a range of applications in collaboration with agencies in the USA and Canada over the past decade, such as CCRS, CFS, AICWR, NASA LEDAPS, BOREAS and MODIS Science Teams, and as a contribution to the North American Carbon Program [1-7]. The algorithm generates a variety of BSI products, such as land cover, biomass, stand and crown volume, stem density, height, crown closure, leaf area index (LAI) and branch area, crown dimension, productivity, topographic correction and validation, structural change from harvest, forest fires and mountain pine beetle damage assessment, and water / hydrology applications. BIOPHYS-MFM has been applied in different locations an