This study in the doctrine of God, with special reference to the thought of John Macquarrie and Charles Hartshorne, addresses the issue of the relational problematic and suggests a potential resolution. The 'Relational Problematic' focusses on the notion of aseity and the doctrine of the Trinity. It concerns the ontological conundrum posed by, on the one hand, the insistence that the external relations God has are of no ontological consequence to him, together with, on the other hand, the witness of the Christian tradition that suggests such relations are not, in fact, inconsequential for the being of God. The task of constructing a resolution begins with the ontology of the early Heidegger which is implicitly relational. Thus 'relational ontology' furnishes a hermeneutical key whereby a 'Relational Theology' may be developed. This development involves, first, the analysis of John Macquarrie's existential- ontological theism, which concludes that to speak of God in the language of 'Being' is to speak of the relational being of God. Second, and alongside this, is placed the analysis and discussion of the neoclassical theism of Charles Hartshorne: the pluriform language of Becoming by which God is conceived in process thought has at its base the perception of the essential relatedness of God. But both Macquarrie and Hartshorne have as a common problem the question of the "entitative status" of God. The solution is suggested by way of conceiving God as "Relational Entity" . The 'Being' and the 'Becoming' of God are manifest in ad extra relatedness: such relationality forms the fundamental ontological motif in the conception of God. This relational perspective frames the resolution to the relational problematic. Aseity is reinterpreted in the light of the relational context of God: God is existentially prior, but not relationally self-sufficient. Trinity is interpreted in terms of relational identity: the necessary ad extra relatedness of God is manifest in three particular patterns of relating. 'God' is thus ontologically conceived as singular relational entity manifesting threefold relational identity.