Consult Australia have examined the benefits of an integrated and collaborative project management approach to Business Case development in their report, Business Case Development in Australia.

The report seeks to make case for an integrated Business Case process through collaborative behaviours across project teams by demonstrating how this approach delivers better outcomes. Particular attention is given to the issue of scalability and the potential for the key Business Cases roles required to reflect the complexity and size of the particular project.

A strong evidence based problem definition is identified as the foundation for a compelling Business Case. The report suggests that a strong, integrated process through collaborative behaviours in project management is required to ensure the problem statements are appropriately tested and validated by available data.

The report draws on the experiences of the working group members to provide case studies that represent good practice.

More information here