The polymerization of ethynyltrimethylsilane with {Pd[C = C-Si(CH3)(3))](2)(PPh(3))2} in different complex : monomer ratios has been investigated. Polymers containing Pd(II) have been isolated and characterized by means of X.p.s. and FT i.r. measurements. The insoluble polymers obtained contain Pd sites that are sigma-bonded to the pi-conjugated growth chain and coordinated to the C = C bonds of adjacent chains in a crosslinked structure. The soluble polymers isolated have a linear structure where Pd(II) coordinates through sigma-bonds to the polymeric chains and to OPPh(3) ligands. If NHEt(2) is used as the polymerization solvent, substitution of Si(CH3)(3) by N(C2H5)(2) groups occurs, catalysed by the Pd complex. Comparison of the X.p.s. and g.p.c. measurements and elemental analyses give an estimation of the number of monomer repeat units for every Pd atom.