Tsangnyön Heruka (1452-1507) was an important but nowadays largely forgotten Tibetan yogin. Because of the deliberate madnessthat he engaged in he became known as a "mad yogin". His message is particularly clearly formulated in a collection of songs,attributed to Tsangnyön and compiled by his closest disciples after he passed away. These songs provide us with a unique insightinto the peculiar form of Buddhism that Tsangnyön and his disciples advocated and practised. By looking at the narrative context ofthe songs it is sometimes possible to discern why, when, and where the songs were sung. By also studying the other texts written byTsangnyön and his disciples (i.e. the so-called "School of Tsangnyön") it is possible to obtain a rather precise picture of thisinteresting "alternative" form of Tibetan Buddhism. A study of this unique body of material provides us with much insight into a littleknown historical period, a social milieu, Esoteric Buddhism, and into the network of disciples and patrons around Tsangnyön. Thuswe may gain specific information about this important and influential movement that nowadays is mainly accessible to us indirectly,by means of the hagiographies and songs, attributed to early Kagyu masters such as Milarepa and Marpa that Tsangnyön and hisdisciples compiled and printed. The creators of these texts (i.e. Tsangnyön and his disciples) have so far remained obscure andunknown. This research project aims at changing this situation.