WebFlow is a a scalable, high level, commodity standards based HPDC system that integrates a High-level front-ends for visual programming, steering, run-time data analysis and visualization, and collaboration built on top of the Web and OO commodity standards. This is combined with a Distributed object-based, scalable, and reusable Web server and Object broker Middleware and a High Performance Backend implemented using the metacomputing toolkit of Globus.