  I discuss the classical cosmological tests-- angular size-redshift,
flux-redshift, and galaxy number counts-- in the light of the cosmology
prescribed by the intepretation of CMB anisotropies. The discussion is somewhat
of a primer for physicists, with emphasis upon the possible systematic
uncertainties in the observations and their interpretation. Given the curious
composition of the Universe inherent in the emerging cosmological model, I
stress the value of searching for inconsistencies rather than concordance, and
suggest that the prevailing mood of triumphalism in cosmology is premature.
