How many integration systems can an ISU be assigned to concurrently?

The Integration System User (ISU) in Workday is a specialized user account designed for automation and system-level integrations. It can be assigned to any number of integration systems concurrently — there is no limit.

From Workday documentation and Pro training:

“A single ISU can be assigned to multiple integration systems across tenants and environments, provided it has the correct permissions and security group assignments. Workday does not impose a hard limit on the number of systems an ISU can be linked to.”

This design provides scalability for environments with multiple integrations (e.g., EIBs, Core Connectors, Studio integrations) without needing to create redundant users.

Incorrect Options Explained:

A, B, C: These options imply arbitrary limits (one, three, five), which do not exist in Workday's ISU architecture.