The catalytic potential of bismuth subsalicylate (BiSub), a commercial drug, for ring-opening polymerization of l-lactide was explored by variation of cocatalyst and polymerization time. Various monofunctional phenols or carboxylic acids, aromatic ortho-hydroxy acids, and diphenols were examined as potential cocatalysts. 2,2′-Dihydroxybiphenyl proved to be the most successful cocatalyst yielding weight average molecular weights (uncorrected Mw values up to 185,000) after optimization of reaction time and temperature. Prolonged heating (>1-2 h) depending on catalyst concentration) caused thermal degradation. In polymerization experiments with various commercial Bi(III) salts a better alternative to BiSub was not found. By means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry a couple of unusual and unexpected transesterification reactions were discovered. Finally, the effectiveness of several antioxidants and potential catalyst poisons was explored, and triphenylphosphine was found to be an effective catalyst poison.