The Long Explanation of the Noble Perfection of Wisdom in One Hundred Thousand, Twenty-Five Thousand, and Eighteen Thousand Lines is a detailed explanation of the Long Perfection of Wisdom sūtras, presenting a structural framework for them that is relatively easy to understand in comparison to most other commentaries based on Maitreya-Asaṅga’s Ornament for the Clear Realizations. After a detailed, word-by-word explanation of the introductory chapter common to all three sūtras, it explains the structure they also all share in terms of the three approaches or “gateways”‍—brief, intermediate, and detailed‍—ending with an explanation of the passage known as the “Maitreya chapter” found only in the Eighteen Thousand Line and sūtras. It goes by many different titles, and its authorship has never been conclusively determined, some Tibetans believing it to be by Vasubandhu, and others that it is by Daṃṣṭrāsena.