  We show that the sets of $d$-dimensional Latin hypercubes over a non-empty
set $X$, with $d$ running over the positive integers, determine an operad which
is isomorphic to a sub-operad of the endomorphism operad of $X$. We generalise
this to categories with finite products, and then further to internal versions
for certain Cartesian closed monoidal categories with pullbacks.
