Hydrolysis-condensation of butyltin triisopropoxide and butyltin tri-tert-amyloxide with more than three water molecules per tin atom yields only the cagelike oxo-hydroxo butyltin cluster,{(BuSn) l2014 (oH) 6)(oH) 2. Its molecular structure has been resolved by X-ray diffraction in the crystalline compound {(BuSn) 12@ 3-0) 14@ 2-OH) 6}(0H) 2 (HOPri) 4. This cluster has also been characterized in solution by Il9Sn,'H, and I3C NMR spectroscopies. ...