The major Indian treatise on Buddha nature is the Ratnagotravibhaga, also known as the Uttaratantra, and it is this core text that Klaus-Dieter Mathes focuses on in this book. Mathes demonstrates how its author, Gö Lotsawa, ties the teachings on Buddha nature in with mainstream Mahayana thought while avoiding the pitfalls of the zhentong approach favored by the Jonang tradition. He also evaluates Gö Lotsawa’s position on Buddha nature against the background of interpretations by masters of the Kagyü, Nyingma, and Jonang schools.