Book 16 explores the less common presentations, that generally relate to a loss of structural symmetry, primarily due to malformation and traumatic events, or unusual compensations. While such advanced analysis and adjusting techniques may initially appear to deviate from conventional Gonstead principles, they actually all adhere to Dr Gonstead’s biomechanical understanding of the spine and pelvis, and their compensatory reactions to a given subluxation state. Adjusting techniques and management approaches are described in Book 16 for many of these less common presentations.