  Alan Guth introduced cosmologists to inflation at the 1980 Texas Symposium.
Since, inflation has had almost as much impact on cosmology as the big-bang
model itself. However, unlike the big-bang model, it has little observational
support. Hopefully, that situation is about to change as a variety and
abundance of data begin to test inflation in a significant way. The
observations that are putting inflation to test involve the formation of
structure in the Universe, especially measurements of the anisotropy of the
cosmic background radiation. The cold dark matter models of structure formation
motivated by inflation are holding up well as the observational tests become
sharper. In the next decade inflation will be tested even more significantly,
with more precise measurements of CBR anisotropy, the mean density of the
Universe, the Hubble constant, and the distribution of matter, as well as
sensitive searches for the nonbaryonic dark matter predicted to exist by
inflation. As an optimist I believe that we may be well on our way to a
standard cosmology that includes inflation and extends back to around 10^{-32}
sec, providing an important window on the earliest moments and fundamental
physics.
