Islamic hermeneutical works commonly state that "the Qur'an explains itself", and scholars inside and outside the tradition have tended to note and/or adopt this intratextual approach to interpretation. Most famously articulated by Ibn Taymiyya, the principle remains in need of interrogation and elaboration. More broadly, the study of Quranic hermeneutics (usul al-tafsir) is receiving fresh attention both in Western academia and in Muslim confessional scholarship. This study is designed to contribute to these developments and the wider concerns of Tafsir Studies. The research examines the extent to which the process of "tafsir of the Qur'an through the Qur'an" (TQQ) has been elaborated in theory and how it has manifested in exegetical practice. The latter is achieved through an extensive case study which compares the approaches and conclusions of a range of exegetes, particularly those whose projects were based solely or primarily upon TQQ. Following these descriptive chapters, the remainder of the thesis works towards a constructive account of TQQ of benefit to any interpreter of the Qur'an, drawn mainly from 'ulum al-Qur'an literature. The theoretical underpinnings of the endeavour are explored in the light of four 'principles', along with classical theories (such as contextual revelation, abrogation) which could present a challenge to the very possibility of intraquranic exegesis. The final chapter draws upon broader genres of literature on the Qur'an which shed light on TQQ processes and practices. Throughout these explorations of theory, method and practical application, a number of core issues and tensions come to light - such as objectivity vs. subjectivity, reductionism vs. pluralism, and the relative authority and value of this form of exegesis in the broader field of tafsir.