Our concern is to offer support to the entire spectrum of staff wishing to nurture the development of early years science, from unqualified personnel through to early years professionals who may hold any one of the plethora of relevant qualifications. We reflect on what form that science might take, bearing in mind criticisms of science education in the early years (taken as 3-7 years in this paper). As a starting point, the proficiencies deemed desirable for science in general and the youngest age group in particular are reviewed. We analyse the shift from the historical concept-process dichotomy to the prescription for inclusion of epistemic and social perspectives, together with the Nature of Science advocacy. A developmental assessment profile provides a means of reviewing early years holistic priorities towards an authentic bottom-up science in which children ask themselves how they came to know and believe the things they do.