We would understand if a Chief Learning Officer who uses a SumTotal LMS in an organization where ADP is the system of record for employee information might wonder why SumTotal can't automatically connect to ADP. After all, ADP is the world's largest HR software company. It has been the payroll system of choice for the majority of companies for decades, and many companies use its integrated HRMS. But a few years ago, when large businesses were clamoring for a single unified HR system, ADP developed a complete talent management system, including learning management.