Traditionally gnawa musicians in Morocco played for all-night ceremonies where communities gathered to invite spirits to heal mental, physical, and social ills untreatable by other means. Now gnawa music can be heard on the streets of Marrakech, at festivals in Essaouira, in Fez's cafes, in Casablanca's nightclubs, and in the bars of Rabat. As it moves further and further from its origins as ritual music and listeners seek new opportunities to hear performances, musicians are challenged to adapt to new tastes while competing for potential clients and performance engagements. Christopher Witulski explores how gnawa musicians straddle popular and ritual boundaries to assert, negotiate, and perform their authenticity in this rich ethnography of Moroccan music. Witulski introduces readers to gnawa performers, their friends, the places where they play, and the people they play for. He emphasizes the specific strategies performers use to define themselves and their multiple identities as Muslims, Moroccans, and traditional musicians. The Gnawa Lions reveals a shifting terrain of music, ritual, and belief that follows the negotiation of musical authenticity, popular demand, and economic opportunity.