In 2002 Donald Rumsfeld was ridiculed for his infamous “known unknown” speech. However, despite the ridicule he was in fact quoting an accepted project management theory. That of managing unk-unks.

unk-unks n. especially in engineering, something, such as a problem, that has not been and could not have been imagined or anticipated; an unknown unknown.

Reports that say that something hasn’t happened are always interesting to me, because as we know, there are “known knowns”; there are things we know we know. We also know there are “known unknowns”; that is to say we know there are some things we do not know. But there are also “unknown unknowns” — the ones we don’t know we don’t know.’

When NASA were working on the Apollo programme they realized that, despite their considerable expertise, they had a lot of new problems to solve – including some problems that hadn’t been identified. And because they knew that once the astronauts were in space/on the moon it would be too late to discover they hadn’t thought of something NASA coined the term unk-unk. The engineers then focused on identifying all the unk-unks and solving them before blast off.

With most software projects you are also faced with unk-unks. After all if you’re not solving a new problem why are you writing code? So what should you do about it?

Well you really only have two options. Either, you hedged against by developing on parallel lines and hope that one works out. This is the approach many designers take – they prototype lots of ideas knowing that only one will be picked, and no one can predict which one before all have been seen. Alternatively you can manage the unk unks as they emerge, by changing the approach in response to new information.

If you want to take this second approach then the team needs to be empowered to solve problems en route (rather than only being allowed to build to an existing design and plan). However, in my experience the senior management and/or product owner must also be intimately involved in the project, have sufficient knowledge to check the plausibility of changes, and be supportive of the mid-course corrections.

The project also need to be managed and structured to allow this to happen. And this means the project needs adopt an adaptive, agile methodology, such as Scrum. So the project team are encouraged to solve problems in little steps as they arise and adapt as they learn more.