Despite the complexity of memory and its diverse manifestations in our daily lives, certain mnemonic effects appear to hold across a wide range of conditions. We identify the effects of recency, contiguity, similarity, primacy, and repetition as potential laws of memory, evaluating their explanatory scope and discussing their theoretical significance. We show that apparent violations of these laws occur when different effects come into conflict, as in the situation of opposing physical forces. We see the search for law-like phenomena as guiding the development and refinement of integrative memory theories.