Passing on your values will also be important. In their now classic book, Built to Last: Successful Habits of Visionary Companies, James Collins and Jerry Porras examined 18 'visionary companies', such as Disney, Wal-Mart and Ford. The companies were world famous, had a stellar brand and were at least 50 years old.
The chief thing they had in common was an almost cult-like devotion to a 'core ideology'. These core values gave each company a unique identity. The company might shift from one product to another, it might completely reorganise itself, but it retained its fundamental identity. Here seemed to lie their secret of success.
Can you think of examples where much the same has been true of individual churches? The church has flourished over many years, it has changed and adapted to new circumstances, but throughout it has kept the same core values (whether explicitly articulated or not). Some of the monastic traditions demonstrate this particularly well.
Might retaining a core identity prove to be part of the story for fruitful and sustainable fresh expressions? They will start with an explicit set of values, perhaps developed in the course of 'thinking ahead'. These values may be revised in the light of experience.
They then become central to the life of the new Christian community, shaping its identity. One generation of leaders passes them on to the next. Might sustainability be about developing an enduring identity?
This is a fascinating topic. In the Anglican church, for example, 'identity' and core values have often been passed down in and through the liturgy. In contrast, some other denominations use statements of faith as their identity base. It will be interesting to see whether a consensus of practice emerges among fresh expressions about how identity endures.
Sue Hope, Priest in charge St Paul's Shipley and Adviser in Evangelism for the Bradford Diocese