The paper outlines a new approach to cross-direction (CD) and machine-
direction (MD) control. The basic idea is to consider the wet-end proc
ess as a two-dimensional (2D) dynamical system in which the CD and MD
are two mutually dependent dynamical processes. The elements of a new
control theory for such 2-D processes are presented together with disc
ussion of possible applications to the CD/MD regulation problem.