This readable introduction to particle physics and cosmology discusses the interaction of these two fundamental branches of physics and considers recent advances beyond the standard models. Eight chapters comprise a brief introduction to the gauge theories of the strong and the electroweak interactions, the so-called grand unified theories, and general relativity. Ten more chapters address recent concepts such as composite fermions and bosons, supersymmetry, quantum gravity, supergravity, and strings theories, and relate them to modern cosmology and experimental astronomy.