ABSTRACT: We present an overview of part of our work on minimal paths. Introduced first in order to find the global minimum of active contours' energy using Fast Marching  \cite{cohen-kimmel:97}, we have then used minimal paths for finding multiple contours for contour completion from points or curves in 2D or 3D images. Some variations allow to decrease computation time, make easier initialization and centering a path in a tubular structure.  Fast Marching is also an efficient way to solve balloon model evolution using level sets. We show applications like for road and vessel segmentation and for virtual endoscopy.