A simple recursive algorithm is presented based on the method of lines for the analysis of multilayered multiple microstrip lines or slots. Our previously proposed scheme of vertical multi-subregion space discretization is used to enhance the numerical accuracy. The recursive formulation is extended to model composite substrates which is aimed at reducing the unwanted coupling among different lines in M(H)MIC's and high-speed interconnects, Numerical results are shown for both quasistatic and hybrid-mode analyses. Results of multiple strips on a composite uniaxial anisotropic substrate are also presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>