Goal of this communication is to report about a recent study on several different biological samples: bone, cartilage, tendon, tumoral tissues. We show that is possible to couple SHIM (Second-harmonic imaging microscopy) and 2PEM (2Photon excitation microscopy) in a powerful way including polarization properties. SHIM on a laser-scanning system is a unique tool for high-resolution, high-contrast, three-dimensional studies of live cell and tissue architecture. The physical origin of SHG within these tissues is addressed and is attributed to the laser interaction with dipolar protein structures that is enhanced by the intrinsic chirality of the protein helices [2]. Although is a coherent process the multiple scattering through the tissue give us the capability to acquire signal in both backward and forward direction [3]. The orientation of collagen fibers within tissues such as tendons or ligaments is of primary importance. In this study, we propose a simple method based on second harmonic generation (SHG) microscopy to map, pixel by pixel, the orientation of the symmetry axis of the second-order nonlinear susceptibility tensor of collagen fibers of a tendon. The method uses only few images acquired at specific polarizations of the input laser beam. In addition to orientation information, the method would provide polarization independent images and an estimation of the ratio of the nonlinear susceptibility components. This procedure is implemented in both backward and forward scattering pathway. The approach could allow mapping fiber orientation fields, independently of individual fiber contrast in the SHG image. The relationship between images acquired in forward and backward scattering configuration provides more information about sample organization.[1] P.J. Campagnola et al. Biophys J., 82, 493-508 (2002).[2] W.R. Zipfel et al. Proc. Natl. Acad. Sci. USA 12, 7075-7080(2003).[3] A. Diaspro et al. Proc. SPIE 5, 24-31(2002).