It is valuable when thinking about distant galaxies to be calibrated on the timescales involved. Based on a reasonable set of numbers, i.e., an open cosmology with H0 = 65 and q0 = 0.05, t0 = 15 Gyr, with the lookback time at z ~ 1 is about 50% of t0, while the lookback time to z = 3 is about 11 Gyr. Or, in a way that is better for thinking about formation timescales, the time since recombination to z = 10 is about 1.4 Gyr, to z = 5 is about 2.6 Gyr and to z = 3 is about 3.9 Gyr. The timescales grow somewhat longer with a lambda-universe, with = 0.7 and m = 0.3, and dramatically shorter for an Einstein-de Sitter m = 1 cosmology (giving a rather unrealistically short timescale for galaxy development by z ~ 5 of < 1 Gyr!).