Planar shock compression effects on void formation and cracking in Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass (BMG) are studied in this paper. Cracking was found to be a result of void linkage in some direction deviation from the maximum shear stress plane. Changing the state of the stress inside the BMG sample led to formation of different void distribution. Nucleation of the microvoids was possibly initiated by release of excess free volume under shock wave compression. (c) 2005 Springer Science + Business Media, Inc.