Despite their increasing proliferation and technical variety, existing cloud storage technologies by design lack support for enforcing compliance with regulatory, organizational, or contractual data handling requirements. However, with legislation responding to rising privacy concerns, this becomes a crucial technical capability for cloud storage systems. In this paper, we introduce PRADA, a practical approach to enforce data compliance in key-value based cloud storage systems. To this end, PRADA introduces a transparent data handling layer which enables clients to specify data handling requirements and provides operators with the technical means to adhere to them. The evaluation of our prototype shows that the modest overheads for supporting data handling requirements in cloud storage systems are practical for real-world deployments.