In 1943 occupied Yugoslavia became the scene of ferocious fighting on a large scale as axis forces launched two major anti-guerrilla operations, codenamed “Weiss” and “Schwartz”, in an all-out effort to put an end to the Yugoslav communist resistance. Despite the axis being massively superior in material terms, sometimes even outnumbering their opponents by six to one, both operations ended in failure as the partisans managed to fight their way out of the German trap. Scholarly research concerning these operations almost exclusively aims to explain their outcome by examining German mistakes, while far lessresearch has been conducted with the intent of examining the outcome of the operations from a partisan perspective. The purpose of this study is to investigate whether the partisan success during these operations can be explained by them using the set of methods of force employment which Stephen Biddle calls “the modern system”, and thereby make a first attempt at explaining the outcome of the operations on the tactical and operational level from a partisan point of view. The result of this study shows that the partisan success indeed can be explained by Biddles theory, at least to some extent, but that a more comprehensive study would need to be conducted to fully verify these claims. The study has thus fulfilled its purpose and provides a small but important contribution to the scholarly debate upon which further research can be conducted concerning the partisan successes during 1943.