Venafi posted a recent Forbes article that linked to this presentation at RSA on the critical role that digital keys and certificates play in securing networks.  The typical company relies on close to 24,000 keys and certificates.  Gaining access to a single key or certificate can compromise the security of multiple organizations because internal controls typically trust these without additional inspection.  As the Forbes article explains:

Digital certificates and encryption keys form the backbone of security and privacy online. When those certificates and keys are poorly managed, however, it puts the network and data at risk. Actually, the risk is even greater than if you had no keys and certificates at all, because having them creates a false sense of confidence. The existence of the keys and certificates provides an illusion of security that can make it even easier for attackers to exploit poorly managed keys and certificates.