Microsoft StreamInsight (StreamInsight, for brevity) is a platform for developing and deploying streaming applications. StreamInsight adopts a deterministic stream model that leverages a temporal algebra as the underlying basis for processing longrunning continuous queries. In most streaming applications, continuous query processing demands the ability to cope with high input rates that are characterized by imperfections in event delivery (i.e., incomplete or out-of-order data). StreamInsight is architected to handle imperfections in event delivery, to generate real-time low-latency output, and to provide correctness guarantees on the resultant output. On one hand, streaming operators are similar to their wellunderstood relational counterparts - with a precise algebra as the basis of their behavior. On the other hand, streaming operators are unique in their non-blocking nature, which guarantees low-latency and incremental result delivery. While our deterministic temporal algebra paves...