There are many early sets of rules (vrata) specific to the ascetic practices of particular Tantras, but the first codification of ethical conduct for practitioners of Buddhist Tantra, in general, is found in the Vajraśekhara, a part of the Tattvasaṃgraha group. There, Tantric ethics are codified as five sets of commitments (samaya) connected with the transformation of the five skandhas into five family buddhas. The full systematization of the Buddhist Tantric code of ethics as the avoidance of fourteen major and eight minor infractions appears soon after. This fully developed Tantric code of ethics incorporates earlier Buddhist codes, in particular the tripartite codification of a syncretistic morality systematized in the Bodhisattvabhūmi. The defining characteristic of the Buddhist Tantric code of ethics is the centrality of the unification of wisdom (prajñā) and special feelings of bliss with method (upāya) as an underpinning.