The notion of quantum matrix pairs is defined. These are pairs of matrices
with noncommuting entries, which have the same pattern of internal relation
s, q-commute with each other under matrix multiplication, and are such that
products of powers of the matrices obey the same pattern of internal relat
ions as the original pair. Such matrices appear in an approach by the autho
rs to quantizing gravity in 2 space and 1 time dimensions with negative cos
mological constant on the torus. Explicit examples and transformations whic
h generate new pairs from a given pair are presented.