This paper is a critical discussion of John Dupré's recent defence of promiscuous realism in Part 1 of his The Disorder of Things: Metaphysical Foundations of the Disunity of Science. It also discusses some more general issues in the philosophy of biology and science. Dupré's chief strategy of argumentation appeals to debate within the philosophy of biology, all of which concern the nature of species While the strategy is well motivated, I argue that Dupré's challenge to essentialist and unificationist views about natural kinds is not successful. One conclusion is that an integrative conception of species is a real alternative to Dupré's pluralism. 1 Introduction 2 Traditional scientific realism 3 A statement of promiscuous realism 4 Promiscuous realism and common sense 5 Pluralism and biological taxonomy 6 The irrelevance of the debate over the ontological status of species 7 The species problem 8 Integration vs pluralism 9 Interdisciplinary and intradisciplinary pluralism.