jats:pElectrospun scaffolds mimic the microstructure of structural collagenous tissues and have been widely used in tissue engineering applications. Both brittle cracking and ductile failure have been observed in scaffolds with similarly random fibrous morphology. Finite element analysis can be used to qualitatively examine the mechanics of these differing failure mechanisms. The finite element modeling demonstrates that the noncontinuum deformation of the network structure results in fiber bundle formation and material toughening. Such toughening is accommodated by varying fiber properties, including allowing large failure strains and progressive damage of the fibers.</jats:p>