Unprecedented policy attention to early childhood education internationally has highlighted the crucial need for a skilled early years workforce. Consequently, professional development of early years educators has become a global policy imperative. At the same time, many maintain that professional development research has reached an impasse. In this paper, we offer a new approach to addressing this impasse. In contrast to calls for a redesign of comparative studies of professional development programmes, or for the refinement of researcher-constructed professional development evaluation frameworks, we argue the need to cultivate what we refer to as an "evaluative stance" amongst all involved in making decisions about professional development in the early years--from senior bureaucrats with responsibilities for funding professional development programmes to individual educators with choices about which professional development opportunities to take up. Drawing on three bodies of literature--evaluation capacity-building, personal epistemology and co-production--that, for the most part, have been overlooked with respect to early years professional learning, this paper proposes a conceptual framework to explain why cultivating an evaluative stance in professional development decision-making has rich possibilities for systemic, sustainable and transformative change in early years education.