OpenUP is a lean Unified Process that applies iterative and incremental approaches within a structured lifecycle. OpenUP embraces a pragmatic, agile philosophy that focuses on the collaborative nature of software development. It is a tools-agnostic, low-ceremony process that can be extended to address a broad variety of project types.

Personal effort on an OpenUP project is organized in micro-increments. These represent short units of work that produce a steady, measurable pace of project progress (typically measured in hours or a few days). The process applies intensive collaboration as the system is incrementally developed by a committed, self-organized team. These micro-increments provide an extremely short feedback loop that drives adaptive decisions within each iteration.

OpenUP divides the project into iterations: planned, time-boxed intervals typically measured in weeks. Iterations focus the team on delivering incremental value to stakeholders in a predictable manner. The iteration plan defines what should be delivered within the iteration, and the result is a demo-able or shippable build. OpenUP teams self-organize around how to accomplish iteration objectives and commit to delivering the results. They do that by defining and "pulling" fine-grained tasks from a work items list. OpenUP applies an iteration lifecycle that structures how micro-increments are applied to deliver stable, cohesive builds of the system that incrementally progresses towards the iteration objectives.