This whitepaper looks at how Security Labels are used with XMPP instant messaging, which is a core capability to support Data Centric Security (DCS). The paper starts by setting out the primary requirements and benefits of using security labels with XMPP. It then gives a high-level summary of the model used and illustrates the user experience with Isode’s Swift client to achieve these goals. The rest of the paper goes into technical details of the standards and approaches needed, and how these are addressed by Isode’s product set. This covers client, server and cross-domain capabilities.