Today’s enterprise is under attack. Network-based threats are continually increasing in breadth, volume, and sophistication and represent an existential risk to organizations around the globe. This paper surveys emerging threats, profiles their highly organized perpetrators, and reviews some of the revolutionary technologies that make these attacks so persistent and effective. Finally, it reviews their implications to enterprise security organizations, revealing the critical “new network” elements necessary to defend against these evolving threats, prevent attacks, preserve sensitive assets, and maintain business continuity.