What technique/process do you follow to build the vision for a program?

The process of starting with a vision for any product/feature is conceptually simple, but also eludes many product managers who may be more accustomed to being able to chart a path to "somewhere" rather than have to contemplate where that somewhere is. It helps to demysify and de-romanticize the notion of a vision and talk about exactly what mechanisms you can use to describe it.  

Amazon's famous approach involves using a PRFAQ as one mechanism to describe that vision. The process of developing that, especially the first page PR, forces really helpful thinking about the vision. It helps clarify thinking about what problem we're looking to solve, why that's important to the customer, and why that matters to our business. It also allows us to describe the overall goal, or end-state vision with clarity and purpose, without all the inevitable caveats, phases and ifs/buts that will ultimately follow (in the FAQ section). And most important, it defines who the customers and beneficieries are, and expresses the value proposition through their lens. We use illustrative testimonials from customers to express that in as direct a way as possible. A common challenge is where we have to balance a customer benefit (e.g. makes their work easier) with company benefit (e.g. improves efficiency or more sales) and this allows us to refine this vision taking both into account.  

We also utilize 3-Yr strategy docs as another mechanism that allows us to express a vision when it spans multiple product or functional areas. Not being constrained by near-term challenges allows us to compartmentalize and solve for each area separately and over time. And also be open to evolving that vision over time.  

The use of tenets helps us apply rules to ensure our efforts stay true to that vision. Our tenets go beyond stating the obvious (good UX, speed, reliability etc) and speak directly to what's important and what choices we have made (e.g. we will prioritize fast access to critical info rather than exhaustive access to all, we will prioritize safety over efficiency etc ).  

The first step to building the vision for a product or program is to ensure you have a clear understanding of the organizational goals and how your product or program fits into it. Second, have a good understanding of the market and customer. 

To me the most important piece when I am building the product/program vision is being clear what problems you don't want to solve or what should be out of scope. Once that is clear, use the qualitative and quantitative data at your disposal to identify what needs to be done and what direction you want to head.