StreamInsight is the new Complex Event Processing (CEP) platform from Microsoft. Developers using Microsoft .NET Framework and the embedded query language (LINQ) can develop and deploy CEP applications. PI for StreamInsight is a forthcoming product from OSIsoft which enables access to PI System data from StreamInsight, empowering complex analyses and computations. This presentation will give overview of Microsoft StreamInsight and PI for StreamInsight. An OSIsoft partner will then share their experience developing with StreamInsight and the PI System, including sample use cases and code examples to build a StreamInsight query.