The PSI is a set of web services. They provide a programmatic interface to the Project Server data and functionality. Here’s a high level schematic of the PSI architecture: The server architecture is layered, the PWA tier being the presentation tier...

I am a program manager on the Project team. I work on server and client programmability features such as the new web services API (called the Project Server Interface or PSI), server side events and the client VBA object model. We have made some great...