Public Key Infrastructure or PKI is about building a trusted means of communication over public and private networks. Over the next few years all businesses, large or small, will be dependent on digital signatures and digital certificates. PKI is about securing the movement and access to data and information. PKI addresses threats in the areas of authentication, privacy, integrity, and non-repudiation. As suppliers and customers are more integrated within an enterprise network and systems, PKI becomes an absolute requirement. This article steps the reader through PKI fundamentals and explains how an organization can position itself to plan and deploy PKI in an enterprise.