  The structural properties of elliptical galaxies are consistent with their
formation in a merging hierarchy. In this picture, the role of gaseous
processes and dissipation decreased with increasing mass creating
preferentially rotationally flattend disky ellipticals (and S0s) at lower
luminosities and boxy, anisotropic ellipticals (often with peculiar kinematics)
at higher luminosities. However, gas and dissipation processes must have been
important even in the formation of the most luminous ellipticals. They played
key roles in determining the phase space structure of Es and possibly ensured a
tight fundamental plane. The bulk of the stars in the majority of luminous
cluster ellipticals formed at redshifts above two, likely above three. This
follows from their homogenous colors and line strengths and their essentially
passive evolution with redshift. Low luminosity ellipticals (and probably field
ellipticals) may have had extended star formation histories, possibly
associated with the presence of disks. The star-formation time-scales can
presumably be constrained on the basis of abundance ratios and seem to be
inversely related to galaxy mass. Massive ellipticals are likely to have formed
the bulk of their stars within one Gigayear.
