  The long-awaited promise of studying high-redshift galaxies at long
wavelengths has been partially eclipsed by progress at optical wavelengths,
mostly because of the number of available pixels. It is nonetheless essential
to study optically selected high-redshift galaxies at wavelengths longward of
1\mic, for several reasons. One of the indications from such studies to date is
that interstellar dust (as an absorber of UV photons and re-emitter of IR
photons) plays an energetically significant role at high redshifts, just as it
does in present-day star-forming galaxies. This also provides a strong
motivation for new searches which detect high-redshift galaxies based on IR
observations. Some of these are already succeeding in clarifying our view of
galaxy evolution in the Immature Universe.
