A method for dimensional synthesis of arbitrary planar mechanisms is presented. The method is based on identification of the mutually independent vector loops of the mechanism, and the design equations that fulfil the desired kinematic behaviour are formulated on the basis of these loops. The identification of the branches is done on the basis of a separation of the mechanism into a number of modules (input bodies and Assur groups). As the design equations are strongly nonlinear (involving both dimensions and rotations of bodies), a continuation method is employed for their solution. The method, with the definition and analysis of the initial mechanism, the subdivision of the mechanism into modules, the definition of the desired kinematic behaviour, and the generation and solution of the vector loop equations, has been implemented in a menu-controlled CAD-system called CADME (Computer Aided Design of MEchanisms).