The invention comprises a new and useful process, and appurtenant apparatus, for developing and using workflow applications with decision support. Specifically, the invention includes a decision support engine and a programmatic interface thereto. The decision support engine is a middleware computer program that receives queries from a workflow application, connects to external data sources, executes queries, and returns query results to the workflow application. The programmatic interface allows a developer to integrate business logic and queries into a workflow application that supports decision-making.