It has been 20 years since the approval of the VCD syntax in IEEE Verilog 1364-1995 that enabled industry-wide interoperability for change/debug data. At that time, it suited its purpose well offering an open and efficient way for data producers such as simulators, emulators and prototype boards, to exchange data with consumers such as testers, debuggers, power analysis tools, that need stimulus to drive them or perform analysis and debug on the results. With the size of designs growing from one million to one billion gates, however, this ASCII file based approach is struggling to handle the data exchange requirements of today. This session will discuss the kickoff of the collaboration between Mentor and Cadence to address this industry challenge with an open and efficient Debug Data API (DDA).