This book is the sequel to "Real Reductive Groups I", and emphasizes the more analytical aspects of representation theory, while still retaining its focus on the interaction between algebra, analysis and geometry, like the first volume. It provides a self-contained introduction to abstract representation theory, covering locally compact groups, C- algebras, Von Neuman algebras, direct integral decompositions. In addition, it contains a proof of Harish-Chandra's plancherel theorem. Together, the two volumes comprise a complete introduction to representation theory. Both volumes are based on courses and lectures given by the author over the last 20 years. They are intended for research mathematicians and graduate-level students taking courses in representation theory and mathematical physics.