As in South America, Indonesia's forest peoples are threatened by development and urbanization. The Petalangan people of Riau in the highlands of East Sumatra were down to 20,000 at the time these recordings of private songs, and music and dance from shamanistic healing rituals were made. The Petalangan highly respect their musicians and shamans, who guide them through religious practices rich in symbolism. Weather conditions disperse the community into small bands during part of the years. This cyclic migration and their threatened status add extra intensity to their musical manifestations. The Riau selections begin with xylophone and gong music, most of it performed simply for the entertainment of the players. The music consists of interlocking patterns, sometimes performed by two players who sit facing each other. This intimate, portable music is used at times when the community is dispersed. Next come three selections of more percussive music that would accompany a healing ritual. Hand drums cycle through a variety of rhythms. The shaman plays an iron rattle and sings in a thin, creaky voice as he circulates among the musicians. In each piece, the intensity builds steadily, in one case culminating in squeals of glee from the crowd. The volume concludes with six selections from the Mentawai, an unrelated forest people from Siberut, an island off the west coast of Sumatra. A woman sings two private songs accompanied by her 12-year-old niece on flute. Lyrics improvised to a familiar song convey the feeling of eavesdropping on a person distractedly singing while at work. A moaning chant performed by three older men during a curing ritual conveys a distinctly spiritual mood. Their voices climb into head voice, and ultimately falsetto as they praise a particular bird. The final piece features foot stamping, high-toned drums playing a triplet rhythm, vocal animal imitations, and a single male voice singing a drawn out melody over the top. The trance dance concludes with wild cries suggesting the shaman's communion with the spirit world.