Despite burgeoning research in international entrepreneurship (IE), very little is known about the processes of how entrepreneurs recognize and pursue opportunities in international markets. To provide an answer to this “opportunity process gap,” we drew on the idea sets framework from the entrepreneurship literature to longitudinally examine a serial entrepreneur who achieved international market success with little industry-specific knowledge, networks, and resources. The research demonstrates the efficacy of the new approach as a lens and methodological framework to advance process-driven explanations and research in IE. These preliminary results reveal a new concept labeled here as opportunity portfolio processing, which involves discovery, creation, prototyping, pruning, and broadening of opportunity sets, that underpins the fundamental processes but not previously documented mechanisms in IE. Our study allowed us to induce a set of IE opportunity portfolio measures—volume, flow rate, novelty, magnitude, and geographical coverage—that offers an alternative framework for measuring and predicting IE performance. In developing the arguments, we present six findings including the role of prior history that, taken together, move us closer to an opportunity portfolio perspective in IE.