This paper relates different points concerning defect levels and lattice defects in CuInSe2and the I‐III‐VI2compounds. First, we review the main levels observed. Second, we propose a hypothesis concerning the electrical compensation processes acting in the I‐III‐VI2materials. Third, we discuss the nature of the defects responsible for the levels, and improve interpretations, by carrying out the deformation potential in antisite defects. Especially, these calculations reinforce the idea that the ‘‘hydrogenic‐type’’ acceptor observed in the I‐III‐VI2materials must rather be attributed to the Cu or Ag vacancy than to an antisite defect.