It shouldn't be rocket-science, but Harvard Business School have concluded that the key to successful family business succession planning is... drum roll... COMMUNICATION!
Based on my experience of working with family businesses, the question of succession is asked all too late, leaving the incumbent generation with the unenviable prospect of working into their 70s before the next generation is ready.
The solution therefore seems to be to start talking about succession as early as possible, given that a well-planned succession can take 5-10 years to plan and implement.
I've also heard from a few clients that setting the time aside from "normal" family time to have these conversations is also important, as it allows families to maintain a separation between their personal and business lives; a line that is all too often crossed or even completely smudged out.
A good start (if you don't know where to start) is to use your professional advisors. We can facilitate meetings to start to explore the options available and better understand/develop your longer term objectives.
What makes a family business successful through generations and decades? It all boils down to communication.