Building on her seminal contribution to social theory in Culture and agency, Margaret Archer develops here her morphogenetic approach, applying it to the problem of structure and agency. Since structure and agency constitute different levels of stratified social reality, each possesses distinctive emergent properties which are real and causally efficacious but irreducible to one another. The problem, therefore, is shown to be how to link the two rather than conflate them, as has been common practice - whether in upwards conflation (by the aggregation of individual acts) downwards conflation (through the structural orchestration of agents), or, more recently, in central conflation which holds the two to be mutually constitutive and thus precludes any examination of their interplay by eliding them. Realist social theory: the morphogenetic approach thus not only rejects methodological individualism and collectivism, but argues that the debate between them has been replaced by a new one between elisionary theorizing (such as Giddens' structuration theory) and the emergentist theories based on a realist ontology of the social world. The morphogenetic approach is the sociological complement of transcendental realism, and together they provide a basis for non-conflationary theorizing which is also of direct utility to the practising social analyst.