The modclling of plasma outfiows from central gravitatingobjects such as AGN is bricfly discussed via analytic examples in thecontext of ideal MHD. The exact solutions are produced via a nonlinearseparation of the variables in the full set of the MHD equations. Attentionis given to the questions of initial acceleration and collimationof the outflow. A quantitative: criterion is provided for the transition ofthe morphologies from highly collimated jets to non collimated winds.