The inflow and infiltration tools in FlowWorks software simplify many of the tasks required in I&I analysis, preventing errors. For each storm event, the program takes into account groundwater infiltration and base sanitary flow, collectively known as dry weather flow, and subtracts it from the total flow in the sanitary sewer to come up with rainfall-induced I&I. Once an adequate number of storm events have been accumulated, the program plots an I&I envelope or the Q vs. I relationship, providing the relationship between I&I and rainfall so that return period based I&I flows can be estimated. All I&I analysis data can be saved for later reference or comparison, and can be published for any audience, public or private. 206/859-6999; www.flowworks.com.