Several texts (both sutric and tantric) have been written on them, not the least of which are Shantideva's Bodhicaryavatara and Ngulchu Thogme's 37 Bodhisattva Practices.
Was wondering how the various schools approach and teach the Perfections, as my experience is primarily Ka-Nying but I like to keep things Rimé. Often it seems that they're not given enough importance, with things like yidam practice and the completion stage yogas being given more of the spotlight.
His Eminence Tai Situ Rinpoche had this to say:
The six paramitas are generally the practice of a bodhisattva—it is a practice of the Mahayana and is taught in the sutras. At the same time, the six paramitas, all aspects of it actually, have to be part of the practice in the Theravada as well as Vajrayana, although it is part of the practice of Mahayana.
In order to overcome all of the karma, and even the habit of that, even the lightest, most transparent subtle imprint of it, you have to transform and then truly become what you ultimately are, which is the embodiment of primordial wisdom; limitless, free of all dualism and triplicity. So for that the six paramitas are practiced.
The full teaching transcript can be found here: http://www.greatliberation.org/library/monthly-teachings-library/monthly-teachings/t14r82387/