Predictions of deep levels associated with N vacancies in AlxGa1−xN as functions of alloy compositionxexplain both (i) the dramatic change from naturallyn‐type to semi‐insulating behavior (forx=xc&bartil;0.5) in terms of a shallow‐deep transition for the vacancy’sT2level, and (ii) the major photoluminescence feature in terms of recombination from the vacancy’sA1deep level. Extrinisic photoluminescence data for Zn‐doped AlxGa1−xN are interpreted in terms of a transition from the conduction band to aT2‐symmetric deep level in the lower part of the gap. This level is associated with antisite Zn on a N site, ZnN.