The analysis of eight years of lunar laser ranging data yields a valaue for the tidally induced secular acceleration of the lunar orbital longitude of n˙=-23.8¿4''/century2. For semidiurnal tidal frequencies this corresponds to a terrestrial Q=12¿2. The error in n˙ is dominated by noise in the data and its modeling. The error is expected to decrease significantly as future data become available and it may become possible to detect an 18.6 yr periodic modulation of the acceleration which would allow the separation of the effects of diurnal and semidiurnal tides. Comparison of n˙ given here with values published from the analysis of classical astronomical observations does not show a significant difference which can be attributed to a changing gravitational constant.