The titanium complexes with one (1a, 1b, 1c) and two (2a, 2b) dialkanolamine ligands were used as initiators in the ring-opening polymerization (ROP) of e-caprolactone. Titanocanes 1a and 1b initiated living ROP of e-caprolactone affording polymers whose number-average molecular weights (M n ) increased in direct proportion to monomer conversion (M n 30,000 g mol À1 ) in agreement with calculated values, and were inversely proportional to initiator concentration, while the molecular weight distribution stayed narrow throughout the polymerization (M w /M n 1.2 up to 80% monomer conversion). 1 H-NMR and MALDI-TOF-MS studies of the obtained poly(e-caprolactone)s revealed the presence of an isopropoxy group originated from the initiator at the polymer termini, indicating that the polymerization takes place exclusively at the Ti-O i Pr bond of the catalyst. The higher molecular weight polymers (M n 70,000 g mol À1 ) with reasonable MWD (M w /M n 1.6) were synthesized by living ROP of e-caprolactone using spirobititanocanes (2a, 2b) and titanocane 1c as initiators. The latter catalysts, according MALDI-TOF-MS data, afford poly(e-caprolactone)s with almost equal content of a,x-dihydroxyl-and ahydroxyl-x(carboxylic acid)-terminated chains arising due to monomer insertion into ''Ti-O'' bond of dialkanolamine ligand and from initiation via traces of water, respectively.