This thesis commences with the premise that while design practices may be said to have a very long, perhaps ancient, history, ‘Design’ as a discipline is of more recent origin, while ‘Design Research’ as a disciplinary practice emerged mid-way through the twentieth century. This inquiry is concerned with the discipline of design from the perspective of the emergence during the past half century of design research, with particular focus on the development of design research theories. The research sets out from the well-established premise that the discipline of design is heterogeneous, with diverse paradigmatic claims as to its epistemological ground, with a concomitant range of ontological implications for what is considered to be within the disciplinary domain of design. In tracing a genealogy of the emergence of design research theories from the 1960s, the research recognises the early predominance of design science and positivist frameworks in defining the disciplinary boundaries of design. Given the predominance of design science within frameworks of formal attempts to define design research theories, approaches to the heterogeneity of the field were concerned with defining a unified field through meta- or supra- categorisation. The emergence of cybernetics and computational analysis in design processes strengthened this position. The thesis recognises a fundamental dualism that has tended to define the heterogeneity of the field, dividing it between design science and design aesthetic, with the former more easily engaged in defining formal design research theories and the latter more easily working in atheoretical emphasises on individual expression and intuition. The project adopts a critical hermeneutics in order to approach analyses of design research theories with an aim to maintain a heterogeneity to the field while yet recognising a series of primordial structures that construe relationality across diverse frameworks. In undertaking this, two competing understandings of ‘ontology’ are engaged with, one opening particularly to ontology as a questioning of the grounding (the meaning of the being) of entities categorised as design, the other emerging from knowledge engineering and computational science, that understands ontology in the formal and syntactical sense of categorisation and hierarchisation. With a critical hermeneutics of design theories, the former understanding of ontology is foregrounded; with respect to engaging with information hermeneutics and semantic web capabilities for information relationality and retrieval, the latter framework is recognised. A key part of this process has been an investigation through the prototype development of a web deliverable design research resource framework to enable researchers to review and cross-reference at a granulated level the models, structures and key terms of a wide range of design research theories. In this respect, the thesis deals with comparative analyses of twenty key design research theories that have emerged over the past half century. A second hermeneutical engagement elicits a series of deep structural relations that work across these theories, eschewing a project aimed at meta-theoretical unification. Correlations are then sought with the literature in the broader understanding of theories of research, as well as information hermeneutics. The project recognises that the discipline of design has matured to the extent that it currently seeks to define its foundational frameworks from within an implicit recognition of its disciplinary integrity and identity. A Mnemotechne of Design, envisaged through semantic web technologies, aims to overcome the dualistic thinking that has dominated design discourses in a project that serves design researchers in assaying the plurality of methodological frameworks that have emerged in the discipline’s approaches to research theories.