Phases > Inception


The overriding goal of the inception phase is to achieve concurrence among all stakeholders on the lifecycle objectives for the project.  The inception phase is of significance primarily for new development efforts, in which there are significant business and requirements risks which must be addressed before the project can proceed. For projects focused on enhancements to an existing system, the inception phase is more brief, but is still focused on ensuring that the project is both worth doing and possible to do.

The primary objectives of the inception phase include:

  • Establishing the project's software scope and boundary conditions, including an operational vision, acceptance criteria and what is intended to be in the product and what is not.
  • Discriminating the critical use cases of the system, the primary scenarios of operation that will drive the major design trade-offs.
  • Exhibiting, and maybe demonstrating, at least one candidate architecture against some of the primary scenarios
  • Estimating the overall cost and schedule for the entire project (and more detailed estimates for the elaboration phase that will immediately follow)
  • Estimating potential risks (the sources of unpredictability) (See Concepts: Risk)
  • Preparing the supporting environment for the project.

Essential activities

  • Formulating the scope of the project. This involves capturing the context and the most important requirements and constraints to such an extent that you can derive acceptance criteria for the end product.
  • Planning and preparing a business case. Evaluating alternatives for risk management, staffing, project plan, and cost/schedule/profitability trade-offs.
  • Synthesizing a candidate architecture, evaluating trade-offs in design, and in make/buy/reuse, so that cost, schedule and resources can be estimated. The aim here is to demonstrate feasibility through some kind of proof of concept. This may take the form of a model which simulates what is required, or an initial prototype which explores what are considered to be the areas of high risk. The prototyping effort during inception should be limited to gaining confidence that a solution is possible - the solution is realized during elaboration and construction.
  • Preparing the environment for the project, assessing the project and the organization, selecting tools, deciding which parts of the process to improve.

Milestone: Lifecycle Objectives

The Lifecycle Objectives Milestone evaluates the basic viability of the project.

Sample Iteration Plan


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Rational Unified Process