La2CuO4 and La2-xBaxCuO4 single crystals have been grown by the travelling-solvent floating zone method. Suitable choice of the growth conditions is very important to obtain high-quality single crystals. It is found that the growth conditions are different for La2CuO4 and La2-xBaxCuO4. The superconducting transition temperatures of La2-xBaxCuO4 samples with different x have been measured. The effect of post-annealing has also been studied. (C) 2002 Elsevier Science B.V. All rights reserved.