This chapter shifts the focus to microlevel environments—that is, encounters—that constrain the operation of corporate and categoric units. Emphasis is placed on the processes operating in all encounters: meeting need states, status-organizing processes, role processes, emotional arousal, symbol and culture use, interpersonal demography, and ecology. These processes, as they unfold in encounters, constrain how corporate units can organize their divisions of labor and how categoric units can sustain beliefs about differences among individuals in societies.