A data space is a governed environment for sharing data across organizations while keeping control over access, privacy, and reuse. Instead of copying information into one central repository, participants expose data through agreed interfaces and common rules. Those rules usually define who may access the data, for what purpose, under which legal basis, and how usage is logged.
In cyber security, data spaces matter because they expand the trust boundary. Every connected node must enforce strong identity, authorization, encryption, audit logging, and provenance checks. If one participant has weak controls, attackers may abuse that path to steal data, inject false records, or consume information outside its intended scope. Defenders use data spaces to reduce ad hoc sharing, limit data exposure, and preserve accountability through policy enforcement and traceability. In practice, a well-designed data space supports interoperability without turning shared data into an open, uncontrolled pool.