This book argues that physics is destined to enter a new era marked by an enlarged conception of physical kwledge. This is t a matter of future discoveries, but has to do with how scientific thought responds over time to what is kwn today. In the new era a genuinely explanatory dimension is restored to physical science which in the current era of thought is quietly abandoned as archaic. The current view is that for a certain class of phemena, physical explanations in the sense of descriptions of underlying causal processes are longer possible. It is assumed that the general demise of classical materialistic causal models (such as the theory of ether as an all-pervading material medium of light propagation) consigns this kind of theorizing to history. This book fully accepts the breakdown of classical causal models, but t the inference that causal explanation itself is outmoded. Instead, it claims that the demise of classical assumptions opens the door on a prospect of thorough causal-physical intelligibility such as was never foreseeable within the classical worldview. Written with the inquisitive and critically- minded layperson in mind, the book describes findings across the major facets of contemporary physics as all pointing to the same conclusion about the nature of physical reality.