Outcome-Based-Selling.com - Business Case Builder

I need to build a business case for a complex solution: can you guide me through the key elements to include to get executive buy-in?

What's the best way to structure a business case that clearly quantifies the ROI and strategic benefits of my proposed solution?

I'm preparing a business case for a strategic project: can you provide a template and examples of how to link the solution to the customer's priorities?

How can I make my business case more compelling to the economic buyer and decision makers? What are some best practices to follow?