  How is the universe organized on large scales? How did this structure evolve
from the unknown initial conditions to the present time? The answers to these
questions will shed light on the cosmology we live in, the amount, composition
and distribution of matter in the universe, the initial spectrum of density
fluctuations, and the formation and evolution of galaxies, clusters of
galaxies, and larger scale structures. I review observational studies of
large-scale structure, describe the peculiar velocity field on large scales,
and present the observational constraints placed on cosmological models and the
mass density of the universe. While major progress has been made over the last
decade, most observational problems in the field of large-scale structure
remain open. I will highlight some of the unsolved problems that seem likely to
be solved in the next decade.
