Abstract In this study a set of numerical analyses of crack growth was performed to elucidate the influence of microcracking on the observed fracture behavior of brittle solids and composites. The random nucleation, orientation and size effects of discrete microcracks and resulting interactions are fully accounted for in a hybrid finite element model. The results indicate that for development of R-curve behavior, the formation of a wake region is necessary. The near-field microcracks are not the sole dominating factor in the development of the R-curve behavior, their interactions can be strongly amplified or mitigated by the far-field cracks. Therefore, the microcrack zone width as well as microcrack density plays an important role in toughening behavior. The continuum description of microcracking can provide a reasonable estimation of shielding; however, it fails to distinguish the effects of microcrack length and the role of the wake region during the crack extension.