Discussion of the supervenience relation in the philosophical literature of recent years has become Byzantine in its intricacy and diversity. Subtle modulations of the basic concept have been tooled and retooled with increasing frequency, until supervenience has lost nearly all its original lustre as a simple and powerful tool for cracking open refractory philosophical problems. I present a conceptual model of the supervenience relation that captures all the important extant concepts (and suggests a few new ones) without ignoring the complexities uncovered during work over the past two decades. I test my analysis by applying it to the problem of defining physicalism, concluding that the thesis of physicalism is best captured by the conjunction of two supervenience relations.