Responsiveness to customer needs is an important goal in agile and lean software development. One major aspect is to have a continuous and smooth flow that quickly delivers value to the customer. In this paper we apply cumulative flow diagrams to visualize the flow of lean software development. The main contribution is the definition of novel measures connected to the diagrams to achieve the following goals: (1) increase throughput and reduce lead-time to achieve high responsiveness to customers' needs and (2) to provide a tracking system that shows the progress/status of software product development. An evaluation of the measures in an industrial case study showed that practitioners found them useful and identify improvements based on the measurements, which were in line with lean and agile principles. Furthermore, the practitioners found the measures useful in seeing the progress of development for complex products where many tasks are executed in parallel. The measures are now an integral part of the improvement work at the studied company. Copyright © 2010 John Wiley & Sons, Ltd.