A micropenetrometer has been developed that produces snow grain bond ruptures at the microstructural level and provides a unique signal for different snow types (Johnson and Schneebeli, 1997; Schneebeli and Johnson, 1998). A micromechanical theory of penetration has been developed and used to recover microstructural and micromechanical parameters for different snow types from the penetration force-distance signal. These parameters are the microstructural element dimension, the mean grain size, the critical microstructural deflection at rupture and the microstructural coefficient of elastic restitution. Additional derived mechanical properties include the compression strength and elastic modulus of microstructural elements and continuum scale volumes of snow. Analysis of the force-distance signal from a Monte Carlo simulation of micropenetration indicates that microstructural and micromechanical parameters may be recovered with an accuracy of better than 5% when spatial and force resolutions are high and the penetrometer tip area is of similar size to the structure dimension.