New evidence of ritual seclusion and sensory deprivation, from the eastern margins of the Namib Desert suggests that specialized shamans may have operated alone, and possibly as itinerants, performing ritual services at widely scattered sites. This behaviour has its origins in hunter-gatherer responses to the introduction of pastoralism, and to the emergence of specialist rainmakers and healers during the second millennium ad. The research reported here identifies and explains important anomalies in the rock art and archaeology of hunter-gatherer religious practice in southern Africa.