The effect of varying catalyst architecture on the microstructure of polymer produced by cis-selective ring-opening metathesis polymn. (ROMP) using cyclometalated ruthenium metathesis catalysts is investigated. A variety of norbornene-deriv. monomers are used to det. tacticity and blockiness of the generated polymer. In addn., the ROMP of several cycloalkenes is investigated. Kinetics studies have been conducted to det. the activity of these catalysts for polymn.