[Slack to the Rescue] Harder Than It Sounds

Introducing slack, very carefully

I don’t know how slack was introduced at Gore, 3M or Google. We at it-agile introduced slack very carefully. We had big discussions about the concept. Though it was very attractive, we feared the costs. Being a company of programmers and consultants, each day a programmer couldn’t program and a consultant couldn’t consult was lost money. Sure, slack should pay off in the long term, but doubts remained.

How to Introduce Slack? – it-agile’s 13.5 %

We started the discussions in 2007, inspired by the stories of Google’s legendary 20 % time. At the end of 2008 we started an experiment, which was a mix between sprint and slack called slant. In one week we wanted to program an entire new product. In preparation we asked all our employees for product ideas and participation. We chose one idea out of a dozen and started with 5 employees, nearly a quarter of our company those days. It was an experiment, far away from Google’s 20 %, but closer to where we were before the experiment.

We failed to deliver the product at the end of the slant. We succeeded in having an ongoing discussion about slack. The discussion continued in 2009 and went on in 2010, where we finally created another experiment: in 2011 every employee should have 20 days free to spent on anything she wants to do. Before that experiment, every it-agile employee already had 10 days for further education, and those 10 days were then included in the slack time. Still far away from Google’s 20 %, but closer to where we were before the experiment: 8.9 % slack.

At the end of 2011 we evaluated our slack experiment. One condition in the experiment was, that whenever someone did something during his slack time, he should add it to his personal slack wiki page. During one of our tuning days where everyone gathers to tune our company, we printed all those slack wiki pages, and arranged them in a gallery. This way everyone could get a good overview of every slack time spent. After that, we decided that the experiment was successful and that we wanted to continue with the concept of slack time.

For 2012 we decided to add another 10 days of slack for every employee. That’s it-agile’s 13.5 % – for now.

How to Evaluate Slack?

It’s very easy to calculate the costs or opportunity costs of slack. (Number of employees) x (number of days of one employees slack time) x (number of the average daily rate) = big pile of money. But since this is an investment you’d expect a return.

We could’ve counted the number of innovations we achieved, but we didn’t do that before or after the experiments. In retrospect, it’s pointless to figure out which innovation came from slack time and which did not. Nobody can tell the relation between slack time and sudden inspiration that hits you in the shower or during your run through the park.

However, we measured slack, not in innovations, but in motivations. Not a single voice was heard during our last evaluation at the end of 2011 that claimed less slack.

Hard to Spend All Your Slack Time

One baffling outcome from our evaluation was: not everybody used every minute of their slack. Truth be told, almost nobody used all their slack. One reason was that over the year dates of work at the customer collided with dates of slack time, and in those cases work at the customer often won. Another reason was that not every planned slack time was actually possible, due to external circumstances like cancelled classes or illnesses.

We learned from this: every it-agile employee is now allowed to use up to 50 % of the unused slack from the previous year in the current year. That means, in 2012 an it-agile employee, given enough slack time left from 2011, is able to use up to 40 days of slack time – almost 2 months of continuous slack.


We’re proud of our slack. We took the risk of doing costly experiments, and, so far, it paid out. We fought long and hard over the details – the concept is so cool and tempting, but the details are so subtle and tricky! -, but we found a solution which works for us. Slack has now a prominent place in our culture, and we’re curious of how the journey continues.

  1. [Slack to the Rescue] What You Want to Do
  2. [Slack to the Rescue] Culture of Autonomy
  3. [Slack to the Rescue] Harder Than It Sounds
  4. [Slack to the Rescue] Forever in Down Under
  5. [Slack to the Rescue] The Future
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About Bernd Schiffer

Bernd Schiffer is consultant, trainer and coach for Agile Software Development in Melbourne, Australia. Learn more about him on his personal homepage, have a look at his company Bold Mover, or contact him on Twitter, Google+, Facebook, XING or LinkedIn.

12 Responses to [Slack to the Rescue] Harder Than It Sounds

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