I have encountered many in the Agile community who love Scrum but seem to hate on the practice of Scrum of Scrums. Others describe their Scrum of Scrums as an overarching meeting of Scrum Masters, or as a meeting for a Product Owner team.
In my experience, however, a Scrum of Scrums is a great way to scale the principle of the Daily Scrum, with the purpose of re-planning development work. If done properly, it's a great practice that implements Scrum’s core principle of bottom-up knowledge creation.
Back to Basics
Let's consider the Daily Scrum first. As the Scrum Guide™ describes, this is an inspect and adapt event for the *Development Team*. It is of the Development Team, held for the Development Team, and run by the Development Team. Only the Development Team members participate in the Daily Scrum. The Scrum Master helps out by teaching the Development Team to have a proper and effective Daily Scrum, reminding them of the purpose of the event, keeping it focused, and sticking to the time-box. The event itself is for the Development Team, and nobody else. The Daily Scrum’s purpose is for the Development Team to inspect and adapt their way towards meeting the Sprint Goal and delivering a potentially releasable increment that delivers value to stakeholders.
Although the Scrum of Scrums is a way to scale the Daily Scrum, the event itself is not a mandatory part of Scrum. It is not defined in the Scrum Guide, and the Scrum Guide is the definition of Scrum -- therefore the Scrum of Scrums is not part of Scrum itself. It is considered “complementary", meaning the practice is not part of Scrum itself, but can be used in addition to Scrum. It is an extension of Scrum for a certain context, respecting Scrum’s underlying principles. Doing a Scrum of Scrums, if it makes sense for your context, is in line with the "ScrumAnd" line of thinking. Actually, you can do it even if it doesn't make sense, and Scrum will help shine transparency on whether the practice helps or not. Having said that, I recommend you try to honor Scrum principles when you implement complementary practices.
Principle-Based Scaling
If we consider that the "Scrum of Scrums" is a way to scale the Daily Scrum, why would the Scrum of Scrums be only Scrum Masters? Why wouldn't it be Development Team centric?
I’ve heard of organizations practicing Scrum of Scrums as if it’s just a status meeting of all the Scrum Teams in an organization, regardless of what product they are on. This doesn’t strike me as a “principle-based” scaling of Scrum. It seems much more like a legacy/waterfall status rollup meeting in my mind. I subscribe to Ken Schwaber’s view that the Scrum of Scrums is for teams who are working together, on the same, integrated product.
I believe and have experienced that a Development Team-focused approach honors the principles behind Scrum, honors the principles of the Daily Scrum practice at the team level, and results in more value being delivered sooner to customers. In my experience, an effective Scrum of Scrums, for and by the Development Teams, leads to a big boost in the Development Teams’ self-organization skills, impediments being removed quicker, higher quality products, and higher valued products delivered sooner.
It would appear that the most credible sources in the industry agree that the Scrum of Scrums should be Development Team focused.
Let’s start with Scrum’s co-creator, Ken Schwaber. In his book, The Enterprise and Scrum, Ken describes the Scrum of Scrums this way:
“Scrum of Scrums are short, daily Scrum meetings at which an engineer from each team working on an integrated product gather to… keep track of progress between parts of the product so that they can more closely monitor any dependency or timing problems.”
Mike Cohn, who has probably trained more Scrum teams than anyone on the planet besides the Scrum creators themselves, has this to say:
"Each team would then also designate one person to attend a scrum of scrums meeting. The decision of who to send should belong to the team. Usually the person chosen should be a technical contributor on the team—a programmer, tester, database administrator, or designer, for example—rather than a ScrumMaster or Product Owner."
Craig Larman and Bos Vodde, who have extensive experience coaching Large Scale Scrum to 500 or more people working on the same product , describe the Scrum of Scrums as a Development Team "coordination technique" that people scaling Scrum should try. They suggest that you avoid turning the Scrum of Scrums into a status meeting or a Scrum Master coordination meeting:
“Avoid...Scrum of Scrums being a status meeting to management... This is where the ScrumMasters meet each other and report their team’s progress to a program manager or a similar role. A Scrum of Scrums—like the Daily Scrum—is a synchronization meeting and not a management status-reporting meeting… Another smell: Scrum of Scrums is a meeting of ScrumMasters at which the ScrumMasters take responsibility for the cross-team coordination. In every case in which we saw this, the ScrumMaster mutated into a project manager within two iterations…"
It’s worth noting that they do go on to suggest that the Scrum Masters meet regularly in a Community of Practice to learn and overcome obstacles – but not to coordinate or synchronize the teams like traditional project managers.
Professional Scrum Trainer and Agile Coach Jesse Houwing confirms the experiences of Larman and Vodde in an email to me:
“Using the Scrum of Scrums as an ‘aggregated status meeting’, whether you’re reporting status to management or just each other, is an ineffective practice. It shouldn’t be about reporting progress against a plan – those are wasteful legacy habits. The important topics for the Scrum of Scrums should be what the Development Teams are doing that might impact others, what they didn’t deliver on time or what they did deliver, but not as agreed previously. It should be about what they’re planning to do and what they need from the other teams. Let’s also not forget that the Scrum of Scrums is also about inspecting and adapting towards reaching the Sprint Goal – just like the Daily Scrum is for each individual Development Team.”
In contrast, there is a scaling approach out there that suggests almost exactly the opposite of what these titans of Scrum suggest. According to their advice, they suggest that Scrum Masters be the attendees at the Scrum of Scrums. I wonder how many Sprints it will be before those Scrum Masters pull a “werewolf” and mutate into old school Project Managers? As a reminder, there is no Project Manager role in Scrum. Further, in my experience, Project Managers typically find it very hard to coordinate technical and other dependencies because they lack the depth of context required to do that effectively. Usually, in my experiences, they just become bottlenecks to progress.
When I coach Scrum teams, I put a strong emphasis on honoring the foundational principles of Scrum when scaling. I encourage Scrum Masters, if they attend the Scrum of Scrums at all, to stand "outside the circle" of Development Team members, and to avoid eye contact with Development Team members as they are collaborating. Because I believe in principle based scaling, it’s probably no surprise to you that I coach the same technique for Scrum Masters at the individual Development Teams’ Daily Scrums too. I want the Development Team members to be empowered to truly self-organize in their coordination and collaboration efforts. Yes, of course I coach the Scrum Masters to be servant-leaders and facilitate as wanted or needed -- but I also encourage them to fade to the background as soon as the Development Team can have an effective Scrum of Scrums on their own.
In Conclusion
A Scrum of Scrums is probably not the only “scaled” Scrum event or technique that you will need on a multi-team, one-product effort. Each of the other optional/complementary “scaled” techniques is worthy of a blog post of its own. On the other hand, maybe not every scaled Scrum implementation needs a Scrum of Scrums event. Your mileage will vary and you will have to inspect and adapt as always.
Ignore the haters and the people who like to treat the Scrum of Scrums as a punching bag. Don’t be afraid to try for an effective Scrum of Scrums. My advice is to assess your own context, to look for practices that you think might work to scale up, but to do so by putting principles first and your best foot forward.
I wish you well and… Scrum On!