The problem of reversing the imaging process, which aims at computing the shape of the imaged scene from one photograph, is referred to as "3D-reconstruction". Many techniques have been designed to solve this problem. Amongst them, the photometric techniques use the relation between the greylevel information and the scene shape. Within the framework of computer vision, the use of this relation in order to compute the scene shape is called "shape-from-shading". In this talk, I will focus on some recent works relating to different aspects of shape-from-shading.