Interreligious dialogue is one of the important ways for overcoming cultural and religious differences and misunderstandings, and for contributing to world peace. But such a dialogue has to go beyond the social, institutional and purely academic areas: it has to reach the very depths of the spiritual, philosophical and theological insights of the religious traditions. In Buddhism, Hinduism and Christianity such insights are expressed in the apparently opposite, but in reality complementary concepts of Void (shunya) and Fullness (purna, in Greek pleroma). These concepts lead to the respective spiritual experiences and their interpretations in scriptures and philosophies. This volume contains the papers presented at an interreligious seminar at Sarnath, Varanasi, organised by the Abhishiktananda Society, and inspired by the ideas and life of Swami Abhishiktananda (1910-1973). These papers throw light on these fundamental concepts from the different traditions, and are an invitation to dialogue. H.H. the Dalai Lama gave the concluding speech on the importance of interreligious dialogue.