Kashmir Shaivism or Trika Shaivism, is a nondualist Hindu tradition of Shaiva-Shakta Tantra which originated in Kashmir sometime after 850 CE. Since this tradition originated in Kashmir it is often called "Kashmiri Shaivism". It later went on to become a pan-Indian movement termed "Trika" (lit. The Trinity) by its great exegete, Abhinavagupta, and particularly flourished in Odisha and Maharashtra. Defining features of the Trika tradition are its idealistic and monistic Pratyabhijna ("Recognition") philosophical system, propounded by Utpaladeva (c. 925–975 CE) and Abhinavagupta (c. 975–1025 CE), and the centrality of the three goddesses Parā, Parāparā, and Aparā.
While Trika draws from numerous Shaiva texts, such as the Shaiva Agamas and the Shaiva and Shakta Tantras, its major scriptural authorities are the Mālinīvijayottara Tantra, the Siddhayogeśvarīmata and the Anāmaka-tantra. Its main exegetical works are those of Abhinavagupta, such as the Tantraloka, Mālinīślokavārttika, and Tantrasāra which are formally an exegesis of the Mālinīvijayottara Tantra, although they also drew heavily on the Kali-based Krama subcategory of the Kulamārga. Another important text of this tradition is the Vijñāna-bhairava-tantra, which focuses on outlining numerous yogic practices.
Kashmir Shaivism shares many parallel points of agreement with the lesser known monistic school of Shaiva Siddhanta as expressed in the Tirumantiram of Tirumular. While also sharing this branch's disagreements with the dualistic Shaiva Siddhanta school of Meykandar, which scholars consider to be normative tantric Shaivism.
Dating from around 850–900 CE, the Shiva Sutras of Vasugupta and Spandakārikā were a Śākta Śaiva attempt to present a non-dualistic metaphysics and gnostic soteriology in opposition to the dualistic exegesis of the Meykandar school of Shaiva Siddhanta, while remaining in agreement with the monistic view expressed in the older and arguably more authoritative Tirumantiram of Tirumular. The Shiva Sutras appeared to Vasugupta in a dream, according to tradition.