According to the BABOK® v3 Guide, the purpose of the task Plan Business Analysis Approach is "to define an appropriate method to conduct Business Analysis activities."

This task is about assessing the initiative from a stakeholder, scope, organizational environment, and expected outcomes perspective. The business analyst may not know everything about the new environment or initiative during the early planning and approach formulation and so it is important to remember that the business analyst can change and update their approach and planning as they learn more during the initiative. However, in the earlier stages of the initiative, it is important to consider which techniques it may be most appropriate to apply based on the knowledge available to the business analyst. 

It is also important for the business analyst to understand any existing methodologies that are followed by the organization or any previously defined and repeatable standard business analysis practices that might be expected by stakeholders. This isn't to say that if there is such a standardized process that the business analyst shouldn't tailor this to suit the needs of a particular initiative.

The key considerations for the business analysis approach is as follows:

• It should be in alignment with the objectives of the change or initiative.
• It should also be aligned and be coordinated to work in harmony with the overall changes and deliverables planned for the initiative.
• It should consider how the approach will cater to tasks to support any risks that may emerge during the initiative. An important aspect of this effort is for the business analyst to repeat processes, techniques, and tools that have proven to work well for the organization.