Tibetan Buddhism (also Indo-Tibetan Buddhism and Sino-Indian Buddhism) is the form of Buddhism practiced in Tibet and Bhutan, where it is the dominant religion. It also has adherents in the regions surrounding the Himalayas (such as Ladakh and Sikkim), in much of Central Asia, in the Southern Siberian regions such as Tuva, and in Mongolia. While each of the four schools is independent and has its own monastic institutions and leaders, they are closely related and intersect, with common contact and dialogue.