This chapter explores the parallels and contrasts between scientific and theological realism. It provides an outline of the various aspects of scientific realism before looking at these in more detail and in comparison to theological realism. The chapter hopes that by this comparison with the well-developed debates between various species of scientific antirealists and realists, some light may be shed on debates concerning realism in theology. It briefly considers each of these three aspects of the scientific realism/antirealism debate before looking at the parallels in the theological realism/antirealism debate. The chapter concludes that metaphysical antirealism faces many obstacles both in science and theology. It considers various claims that are typical of those made by scientific realists. The term 'scientific antirealism' covers both metaphysical/semantic issues and epistemological ones. Epistemological antirealism is typically not called 'antirealism' outside of philosophy of science, but rather 'scepticism'. Religious projectivism proposes that God and other elements of theology are projections of some human or social entity.