Physical realism is the thesis that the world is more or less as present-day physical theory says it is, i.e. a mind-independent reality, that consists fundamentally of physical objects that have causal powers, are located in space and time, belong to natural kinds, and interact causally with each other in various natural kinds of ways. It is thus a modern form of physicalism that takes due account of the natural kinds structure of the world. It is a thesis that many present-day scientific realists would surely accept. Indeed, some might say that physical realism just is scientific realism, but under another name. However, the argument that is presented for physical realism is not the standard one for scientific realism. It is not a two-stage argument from the success of science to the truth of scientific theories to the reality of the entities postulated in these theories. It is more powerful than this, because it is more direct, and its premisses are more secure. It is more direct, because it develops what is basically a physicalist ontology as the only plausible metaphysical explanation of the new scientific image of the world. It is more secure, in that it does not depend, as the standard argument does, on any doubtful generalisations about the nature or role of scientific theory.