Cranial motion is conventionally described through the individual patterns of the bones. That description is useful, but it is not the whole story. What you are palpating is a membrane under tension, breathing.
The reciprocal tension membrane, or RTM, is the dural system that guides and influences cranial bone motion. It is one of the foundational concepts in craniosacral work, and understanding it changes how you hold a skull. This is a short introduction for anyone beginning the study, or for practitioners who want to revisit the fundamentals.
![]()