  Surface-brightness profiles for early-type (S0-Sb) disks exhibit three main
classes (Type I, II, and III). Type II profiles are more common in barred
galaxies, and most of the time appear to be related to the bar's Outer Lindblad
Resonance. Roughly half of barred galaxies in the field have Type II profiles,
but almost none in the Virgo Cluster do; this might be related to ram-pressure
stripping in clusters. A strong \textit{anti}correlation is found between Type
III profiles ("antitruncations") and bars: Type III profiles are most common
when there is no bar, and least common when there is a strong bar.
