For a Deer ALWAYS lung/heart shot, Yes if u do hit them in the head they are out id ratehr be out fast but id also rather not have u shoot at me and blow my jaw or nose off first, just go for the heart or lungs it makes u a better hunter overall in many ppls eyes, squirrels always the head yotes it depends on the range and gun im using if ive got my .22 and hes 60 yards away ehadshot any farther and u dont use a .22 and u go for the lungs and heart, cats well i dun have any around ehre well i feel ive shared my "piece o' pie" Ovr *N* Out