We give several characterizations of the improjective operators, intro
duced by Tarafdar, and we characterize the inessential operators among
the improjective operators. It is an interesting problem whether both
classes of operators coincide in general. A positive answer would pro
vide, for example, an intrinsic characterization of the inessential op
erators. We give several equivalent formulations of this problem and w
e show that the inessential operators acting between certain pairs of
Banach spaces coincide with the improjective operators.