The model calculations considered here test the DWBA with a wide range of three-body models. Each of the calculations, however, considers only one or two aspects of the accuracy of the DWBA. The lack of overlap of the testing parameters limits the con­ clusions which can be drawn. This is particularly true with reference to the nucleon­ core potential where comparable parameters are rarely used. In spite of this limitation, we may make a few observations about the sensitivity of the model cross sections and the mechanism which produces an accurate DWBA. Specifically we may summarize the most important results as follows: 1) In these models the exact DWBA at low energies (E

1. Fundamentals of Three-Body Scattering Theory.- 1.1 Two-Body Scattering.- 1.2 The Simplest Three-Body Problem.- 1.3 Three Distinguishable Particles - Wave Function Approach.- 1.4 The Faddeev Equations (3?3).- 1.5 Bound State Scattering.- 1.6 Unitarity.- 1.7 Identical Particles.- 1.8 Three-Body Scattering With Separable Interactions.- 1.9 Rotationally Invariant Equations for Separable Interactions.- 1.10 Conclusion.- References.- 2. Analytic Structure of On-Shell Three-Body Amplitudes.- 2.1 Background.- 2.2 The Fredholm Representation of On-Shell Amplitudes.- 2.3 Analytic Continuation in Energy of the On-Shell Amplitudes.- 2.4 On-Shell Calculations.- 2.5 Conclusions.- Appendi x.- References.- 3. Theory of Three-Body Final States.- 3.1 The Problem.- 3.2 Coherence.- 3.3 The Two-Body Case.- 3.4 The Three-Body Case.- 3.5 Spinless Boson Example.- 3.6 Implementing Unitarity and Analyticity.- 3.7 Three Identical Bosons Again.- 3.8 Conclusions.- References.- 4. The Boundary Condition Method.- 4.1 Fundamentals.- 4.2 Two-Particle Description.- 4.3 Boundary Conditions for Three-Particle Scattering.- 4.4 The BCF Integral Equation.- 4.5 Practical Evaluation of the Kernel.- 4.6 The Interior Region.- 4.7 Summary of the Formal Work.- 4.8 An Example.- 4.9 Discussion.- References.- 5. A Relativistic Three-Body Theory.- 5.1 Derivation of the Basic Equations - Spinless Case.- 5.2 Spin and Isospin.- 5.3 Physical Input: Blankenbecler-Sugar vs. Feynman, etc.- 5.4 Application of Relativistic Three-Body Formalism.- 5.5 Present Developments - Three-Body Phenomenology.- Appendix A.- Appendix B.- References.- 6. Applications of Three-Body Methods to Many-Body Hadronic Systems.- 6.1 Tests of Reaction Mechanisms.- 6.2 Three-Body Effects in Nuclear Processes.- References.