This document provides an outline on the topic of Sufism. It discusses the problems in defining Sufism, as the term can have different meanings depending on perspective. Sufism was rediscovered by Europeans who saw the mystical elements as non-Islamic. Ibn Khaldun viewed Sufism as belonging to Islam and involving asceticism and seeking knowledge of God. After 1200, Sufism became more institutionalized through saints' tombs and pilgrimages, masters and disciples, and rituals like chanting God's names. However, views of Sufism today range from integral to Islam to being rejected as innovation.