We present high resolution specific heat measurements and thermal expansion data of YBa 2 Cu 3 O 7-δ polycrystalline samples in the temperature range 20–300 K. The specific heat anomaly at T c shows strong deviations from mean field behavior due to superconducting fluctuations. The fluctuation behaviour seems to be more complicated than simply Gaussian. The thermal expansion shows clear anomalies at the T c 's of the samples. Additionally we give an estimate of the Gruneisen functions and discuss data of the low field DC Meissner effect in connection with the grain structure of the samples.
