Observational and theoretical work on bulge dynamics is thriving; increasingly powerful tools provide us with much more information than we had a decade ago. Inevitably, bulge dynamics look more and more complicated. But two simple themes unify this work. One is well known: we see kinematic signatures of triaxiality and of galaxy accretion. This story is familiar from work on elliptical galaxies; I will review it only briefly (section 2). The second theme is not well known; it will be the focus of this paper. A substantial body of evidence shows that some "bulges" are really disks: they have the steep, r1/4-law brightness profiles that we associate with bulges, but they also have the "cold" (rotation-dominated) dynamics of disks. Numerical simulations suggest that they were built by various processes of secular evolution in disks, including inward gas transport by nonaxisymmetries in the potential and vertical heating by resonant scattering of stellar orbits off of bars. The importance of secular evolution driven by interactions with collective phenomena was emphasized by Kormendy (1982a, and references therein); sections 3 - 7 bring these reviews up to date. Just as mergers showed that galaxies evolve not in isolation but in part through interactions, so the evidence for secular dynamical processes implies that internal evolution is more than the aging of stellar populations: the interactions of components can significantly change galaxy structure over a Hubble time.