  We consider conservation of momentum in AQUAL, a field-theoretic extension to
Modified Newtonian Dynamics (MOND). We show that while there is a sense in
which momentum is conserved, it is only if momentum is attributed to the
gravitational field, and thus Newton's third law fails as usually understood.
We contrast this situation with that of Newtonian gravitation on a field
theoretic formulation. We then briefly discuss the situation in TeVeS, a
relativistic theory that has AQUAL as a classical limit.
