Off-resonant effects are a significant source of error in quantum computati
on. This paper presents a group-theoretic proof that off-resonant transitio
ns to the higher levels of a multilevel qubit can be completely prevented i
n principle. This result can be generalized to prevent unwanted transitions
due to qubit-qubit interactions. A simple scheme exploiting dynamic pulse
control techniques is presented that can cancel transitions to higher state
s to arbitrary accuracy.