I recently had to go through a process to identify this for my own, and those I help. Maybe these pointers will help:
PURPOSE (answers the question 'Why?') - THE REASON: guides everything.
- What impact does the organisation/system wish to have on society?
- What is the aim of the organisation/system?
- What is the organisation/system called to accomplish?
(you could use a Word Cloud to collate the answers from all internal and external partners to each of the below, to provide a picture)
- Passion - What do I/we love? + What am I/are we good at?
- Vocation - What am I/are we good at? + What does the world need?
- Profession - What does the world need? + What does the world want?
- Mission - What does the world want? + What do I/we love?
At the intersection of the personal perspective you will find Purpose which in turn should be able to answer the collective perspective questions. Ultimately the individuals make up and inform the whole, and the whole transforms this into something much greater than the sum of it's parts.
NOTE: with this ensure you know the ESSENCE/MEANING (which answers the question "Who?") of the Organisation/System. In other words have a thorough understanding of THE IDENTITY: is everything, of the Organisation/System and how they differ. For this too there is a collective and personal perspective.
This process also lead to my decision to make the Personal Perspective Exercise a permanent feature of the Induction Process, promoting the continual living evolution of the organisation's purpose.
I hope this in some way helps.