This project aims, first, to rethink central issues in the philosophy of biology by elaborating an ontology for biology that takes full account of the processual nature of living systems as an interacting hierarchy of processes at diverse spatial and temporal scales. The concept of a stable biological thing will be analysed as a stabilised process relative to an appropriate time scale, and this conception should make possible a better understanding of familiar biological pluralisms (about genes, organisms, species, etc…) in terms of different ways in which distinct scientific practices intersect with biological processes.Second, the concept of process developed will be used to rethink some further highly topical philosophical issues in contemporary philosophy of science. The processual perspective will be deployed to provide a critique of the widely discussed recent versions of mechanism. The project will explore generally the relevance of this perspective to influential contemporary accounts of causation and explanation, especially those that have been derived from mechanism.Finally the project will apply the preceding ideas to some important areas of contemporary biology: systems biology, synthetic biology, and microbiology. These investigations will be carried on in parallel with the more general philosophical enquiries, with the idea that the two will be mutually informative: the philosophical analyses will not only be applied to scientific concepts, but will also themselves be evaluated for their relevance to real cutting edge biology. This evaluation will be guided by interaction with scientific practitioners and an expert Advisory Board, as well as text-based study. The project aims to be of direct relevance to both philosophy and science.