This paper reports research into developing digital storytelling (DST) to enhance reflection within a specific professional learning context--that of a programme of teacher education--while concomitantly producing a transferrable design framework for adaption into other, similar post-secondary educational contexts. There has been limited substantive, evaluative design-based research investigating empirically the potential of digital storytelling for reflection in professional, post-secondary education. Consequently, there has also been a lack of robust and reusable models to guide and inform design-based research in this context. This paper illustrates the development of a repeated study, undertaken on a longitudinal basis, over 3 years, and on a large scale, involving 323 pre-service teachers. The design-based research developed at the three key stages along the triadic spectrum of maturity: from (1) analysis and exploration, through (2) design and construction, to (3) evaluation and reflection (Kopcha, Schmidt, & McKenney, 2015). The innovation reported here is now a mature intervention, constituting a core part of the professional educational formation of pre-service teachers within a two-year, graduate teacher education programme. Further, the R-NEST design framework, which emerged from this longitudinal design-based research, enumerates key criteria and principles for designing, implementing and evaluating DST to enhance reflective practice in post-secondary professional education.