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What is the evidence for leadership and team effectiveness?

What is the best leadership model? How do we measure effectiveness? What is the evidence for team leadership?

Teams are important. This refrain is frequently repeated online, in books, and across organisations. Despite recognising the centrality of teams, organisations frequently underinvest in them, failing to promote and develop the leadership skills required to unlock the benefits that teams create, as this Gallup study found. Complicating matters further the proliferation of leadership books (over 60,000 on Amazon alone), provide a plethora of theories that offer solutions to unlocking effective leadership and building exceptional teams. These frameworks for team success often provide contradictory ideas at a level of abstraction that makes knowing 'how' to apply them challenging at best. It all begs the question, what actual evidence supports these assertions? Or, for that matter, can any famous football manager, business executive, or military leader sit down and write a best-selling book on leadership? And, to be honest, what does Sir Alex Ferguson know about leadership outside of running an elite football club?

If you've read any of my blog posts, you'll know that I fundamentally believe that the most significant barrier to impact and social change is how organisations and teams function; teams matter in everything from sports to business. But, I've recently been trying to challenge my thinking on how teams work, and I wanted to see the evidence that supports the assertion that leadership is important in team success? And what does it say if that's the case?

As part of Project Oxygen, Google posed a similar question. They wanted to know if managers made a difference and began by assuming that they didn't. They discovered that managers do matter. Gallup research supported Google's finding, which found that managers account for 70% of the difference in employee engagement scores across businesses. These conclusions led Google to turn their findings into a framework for effective leadership, published online as Re:Work. Their management framework led to research on what makes effective teams, set out in the graphic below.

This assessment builds on the broad literature on effective teamwork and engagement. The key authors on leadership and team formation (e.g. Hackman, Ciampa & Watkins, Sinek, Edmondson & Harvey) agree that team performance is driven by team composition (getting the right people on the team), professional development, and team leadership lead to improved team effectiveness. In short, there is a body of evidence demonstrating the significance of leadership in team performance, which translates into organisational effectiveness.

And yet, as I dug into the literature, I also found some interesting research on management and team performance that is less conclusive results. A meta-analysis of 1,390 teams from various healthcare sectors in the United States discovered that team performance and collaboration accounted for less than one-third of patient outcomes. It is still an important factor, but not the majority factor, not 70 per cent, depending on how you look. Furthermore, a recent study at the London School of Economics discovered that while teamwork positively affects organisational performance, it also creates pressures and stresses that harm individuals. As you dig into the concepts and ideas below the surface of macro agreement, what drives team performance varies greatly. It is unclear what actions or activities result in positive team outcomes and what activities cause stress, strain and team failure.

My literature review led me to conclude that there isn't a single repeatable formula. Yes, we can improve management practice and form better teams, but it is always context-dependent as to whether these will succeed. Let us use sports as an example. Why is it that a team can perform exceptionally well one year, even winning the championship (e.g., Leister City in 2015-16, or the Montreal Canadian in 2019-2020), and then collapse the next year with little hope for the players, coaching staff, or wider management? If there is a formula for success, we should expect it to hold year after year if there are no significant changes to the team's composition?

If there is no formula for successful management, is it just down to talent? According to Gallup, natural talent is more important than learned leadership and team effectiveness skills, with only one out of every ten employees in most companies possessing leadership potential, with another two out of ten trainable for better management. If this is the case, we might as well give up on leadership training now. Yet, I don't think it is. Some people are naturally more inclined to create an environment for team effectiveness, while others are predisposed to working alone. And yet when you look across the literature, there is such a mosaic of personality types, skills, and experiences highlighted in teamwork. It can only be that everyone, who wants to, can lead and form an effective team (just look at Leading Quietly by Joseph L. Badaracco).

There must be something else, beyond natural talent, that makes leaders successful at team formation and teams successful. In the Hidden Half by Michael Blastland observes that the "biggest successes are often the least instructional." And yet we rely on them to understand leadership and team effectiveness. Perhaps this is the problem. We're looking in the wrong places to understand team performance and identify the characteristics that make teams successful.

So, what exactly is the unspoken half of leadership? What does it mean to examine the unspoken half of leadership? It entails looking beyond the big theories and meta-analyses to the nuts and bolts of what works for a specific individual and team in a particular context. It necessitates knowledge of these big theories and a willingness and openness to Think Again to use Adam Grant's phrase about what this means for you and leadership daily.

Is there anything we can do if there isn't a single metatheory? From my review of the literature, I believe so.

  1. Familiarise yourself with some of the major frameworks for effective teamwork and leadership. But don't worry! You don't have to read 60,000 books; choose one or two, preferably from different disciplines, that you find interesting and engaging. Ignore the author's instructions to follow each step to the letter, and instead choose and write down the actions that feel right for you. That is the first step.

  2. Experiment. You must be comfortable deploying the concepts you think will work for you, which you'll only accomplish through practice. That means failing, rethinking, and reconsidering how you approach a problem with your team. We need to tell everyone who leads a team that they must accept failure right now! Expect to fail from time to time. The best organisations create support systems around this, but this is not always the case.

  3. Give yourself some wiggle room. If you're going to fail, plan for it. Allow yourself to make mistakes and change course as you learn more about your team, yourself, and the problems you're facing. The approach you began with may not be the best to finish with. Remember that, while you may not be the President of the United States, the problems that come across your desk as a leader will be complicated and unclear; if they weren't, someone on your team would have solved them already.

“What I was quickly discovering about the presidency was that no problem that landed on my desk, foreign or domestic, had a clean, 100 per cent solution. If it had, someone else down the chain of command would have solved it already. Instead, I was constantly dealing with probabilities.” Barack Obama, A Promised Land

That's it, just three steps from the literature to becoming a more effective leader and manager of teams. Determine which aspects of an effective team leader will work for you and align with your values. Experiment with the concepts, and allow yourself room to manoeuvre.

Books you might want to consider:


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