Agree upon a vision and principles of the strategy, and define its goals.
A vision is about what is possible, what the potential is to achieve it, and the ultimate end state. The vision allows you to then clearly define the strategy. If you do not have a clear strategy, it is very easy to lose focus and become distracted by other competing issues or stakeholder demands. It is important to reflect and review the strategy from time to time and be open to amending it as new information is discovered.
It is very important you base your strategy on what you hope to achieve given your current knowledge, stakeholders and resources.
Why it is important
Having a clear vision and principles of the strategy allows you to:
Have agreed goals that can be communicated to others