Abstract: In this paper, an effective numerical approach forinteraction of macrocrack with microcracks in plane elastic media ispresented. By extending Bueckner's principle suited for a single crack to ageneral system containing multiple interacting cracks, the original problemis divided into a homogeneous problem (the one without cracks) subjected toremote loads and a multiple-crack problem in an unloaded body with appliedtractions on the crack surfaces. Thus, the results in terms of the stressintensity factors (SIFs) can be obtained by taking into account the latterproblem, which is analyzed easily by means of the Hybrid DisplacementDiscontinuity Method proposed recently by the author. The examples given byCai and Faber (see, Cai H, and Faber KT. 1992, On the use of approximatemethods for microcrack shielding, ASME J. Appl Mech 59, 497\sim501) for the interaction of a macrocrack withmicrocracks are exemplified here. It is found that the presentapproximation method is very simple andeffective for microcrack shielding problems.