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PRINCE2 - Managing Stage Boundaries (SB) part 4

Updating a Project Business Case (SB3)

Fundamental principles

Projects do not take place in a static environment.
The external environment changes, as do the nature and timing of the project’s products.
The Business Case needs to reflect these changes and must be reviewed and amended to keep it relevant to the project.


The update of the Business Case and the project Plan is a cyclical process during stage-end activities throughout the project.

Process description

The objectives of this sub-process is to revisit and revise, where necessary, the costs, benefits, risks and timings stated in the Business Case.
These may have been affected by internal or external events.

Various factors will affect the sub-process:

  • The final implementation date for the project may have changed, for the better or worse, which might affect some or all of the benefits.
  • The cost of delivering the product might have changed, this affecting the cost side of the cost / benefit analysis.
  • Approved changes will have affected products, hence benefits
  • Externally the corporate or programme environment into which the product will be delivered may have changed
  • The situation with regard to external resources or suppliers may have changed beyond the control of the project
  • An Exception Plan may have caused the Business Case to be revisited

A revised version of the Business Case is created.
The Risk and Issue Logs are examined to see if anything has changed that might affect the Business Case.

It is worth noting that changes may improve the Business Case, as well as weaken it.

The Project Board is usually only authorised to continue while the project remains viable (that is, the benefits will be realised within the cost and time parameters set out in the currently agreed Business Case).

If the costs and / or time are to be exceeded or if it becomes clear that benefits will be substantially lower than those set out in the Business Case, the Project Board need to have the revised Business Case approved again by corporate or programme management.


The Project Manager is responsible for this sub-process assisted by Project Support.
Those with Project Assurance responsibilities should check out the work.

The project’s benefits are a prime responsibility of the customer.

Information needs
Management informationUsageExplanation
Project PlanInputHave any changes to the Project Plan been made that affect the Business Case.
Issue LogUpdateAre there any new Project Issues that threaten (or could improve) the Business Case? Do Business Case changes raise new Project Issues?
Business CaseUpdateRevised to account for any changes to the project that may affect it.
Risk LogUpdateAre there any new risks that threaten the Business Case.

These are given in tabular form in the file ‘SB3 updating a project business case.doc’ in the product package.

Key criteria

  • Has anything happened outside the project that affects the Business Case?
  • Has the Project Plan changed in a way that impacts the Business Case – for example, in terms of overall cost or the date of the scheduled outcome?
  • Has it become impossible to achieve some or all of the identified benefits?

Reviewing the Business Case is best done after the Project Plan has been brought up to date.

It is sensible to review the Business Case after any activities caused by reaction to risks have been added to the new Stage Plan.
These activities or their cost may have an effect on the Business Case.

This product contains EVERYTHING in the publications:

Managing Successful Projects with PRINCE2 - 2005 edition
Managing successful Projects with PRINCE2 – 2009 edition
Directing Projects with PRINCE2.
The Complete Project Management package.

And much more besides - at a fantastic price.