The essay seeks to clarify the features of the Polish resistance movement during the Second World War that differentiate it from international resistance. Borejsza highlights the difficulties of providing an unequivocal definition of the term resistance which comprises not only the dissent against the German and Soviet occupying forces but also the significance of a tradition of struggle and resistance that goes back as far as the Polish insurrection of 1863. The need to face two invaders simultaneously, and the impossibility of taking advantage of allied support, gave rise to a resistance which could "only rely upon its own forces" and involved the whole population. Compared to Italy or Germany, in fact, Poland's resistance was a "mass" struggle. The percentage of the population engaged in forms of active resistance was often greater than that in other occupied lands. "Small" sabotage - as the anti-German resistance was called - was a generalized strategy against the occupier, while the creation of military units (the AK) enabled the coordination of reprisals and resistance which were initially fragmented and therefore ineffective. Though the toll of Polish victims was heavy, equally significant was the scale of the resistance. Diversified in its forms, it continues to provoke historical and political discussion which looks likely to continue unabated.