It is a method created by the American John Friend at the beginning of the 90's.
In class, students apply the universal principles of alignment, whose techniques usually coincide with the taught in the Iyengar Yoga. It includes stories, songs, and vital values of tantric philosophy.
Each class is usually devoted to a theme, which is used as a metaphor to reflect on what is happening in the positions. An important aim of the practice is to open the heart, thus emphasizing tilts backwards.
It is a deeply rooted in United States approach.