Dharmakirti's Sambandhapariksa was already well known through its Tibetan translations and numerous quotations in Sanskrit before a newly found Sanskrit manuscript from Drepung monastery and Hideomi Yaita's identification of the last three strophes in Sanskrit allowed for a new edition of the complete text. This Drepung manuscript also contains the commentary Sambandhapariksavrtti hitherto ascribed to Dharmakirti, but in this manuscript, and well acceptable, ascribed to his pupil Devendrabuddhi. To the critical and diplomatic editions of these texts, a new critical edition of the Tibetan translations of both is added, because Frauwallner for his edition of 1934 could use only the version of Narthang. Subject of Dharmakirti's work is the refutation of all types of relation (sambandha), including the relation of causality, that were assumed by various Indian philosophical systems to exist in reality. For Dharmakirti these are not given in reality (vastutah), but only conceptually constructed (kalpita). In the introduction the import of this refutation for Dharmakirti's logic is highlighted. Thereby a center-piece of the long history of Indian sambandha-reflections from Patanjali and Bhartrhari onwards to Utpaladeva and Abhinavagupta is now available again in its original Sanskrit.