Ethene/propene copolymerizations were performed in solution with a single centre catalyst system composed of a "constrained geometry" half-sandwich organometallic complex {eta(1): eta(5)-[(tert-butylamido)dimethylsilyl](2,3,4,5-tetramethyl-1-cyclopenta dienyl)}titanium dichloride, and methylaluminoxane. The statistical treatment of polymerization data allowed to determine the reactivity ratios for ethene and propane: r(E) = 1.35 +/- 0.09, r(P) = 0.82 +/-0.05, r(E)r(P) = 1.10 +/- 0.14. This catalyst system promotes an almost random distribution of ethene and propene and gives rise to values of r(P) and r(E) very similar to each other.