Lên đồng (lit. "to mount the medium", or "going into trance"; alternately, hầu bóng ("receiving incarnations of the deities") or hầu đồng) is a ritual of spirit mediumship practiced in the Vietnamese indigenous religion and Đạo Mẫu, a Vietnamese mother goddess religion, in which followers become mediums for various deities. Sessions involve a number of artistic elements, such as music, singing, dance and the use of costumes. The invocation songs (Vietnamese: hát văn) used to induce a trance in mediums have been described as a "particularly noteworthy expression of the performing art of the Kinh people"; the lên đồng ritual itself is considered to be an element of Vietnam's intangible cultural heritage.