Although it is possible that your organization has a different impression on what a business case is, the traditional description is a document that provides justification for a change. You can have business cases that are not related to a project effort because not all changes that need to be examined go through the rigor of a project lifecycle. However, that is an outlier condition in my experience. Most business cases are the fundamental first step in getting a project off the ground and facilitates formal change justification to senior leadership.
A business case shouldn't be a manifesto but a somewhat lean document that contains information important to those that are going to approve the change or the next step in a change process. For example, a business case may not have significant details regarding the costs of the change because that information comes later down the road.
Although the business case is an early project management core document, it may need to contain information that extends beyond the project. For example, an IT process that will be improved based upon the introduction of a new application. The ongoing support and maintenance of the new application will likely be valuable in a "go / no go" decision regarding the change. However, ongoing support happens after the project is completed, so it may not be something tracked in the project plan or schedule.
In short, a business case should try to communicate the benefits, costs and potential consequences of a change decision. This often comes in the form of describing the objectives of the endeavor and the impact it will have on the organization. That impact section can include information regarding the impact of making the decision to go ahead, postponing a decision or a decision to reject the change endeavor at this time.
What goes into a business case is a highly subjective decision. Again, I feel that it should be as lean as possible and then be expanded based upon the feedback of the decision makers that will rely upon it. The BABOK v3 sums it up quite nicely.
A business case is used to:
• define the need,
• determine the desired outcomes,
• assess constraints, assumptions, and risks, and
• recommend a solution.
© 2016 Dwayne Wright