A few months ago, I had a difficult conversation with a colleague about a project that had drifted off course. I knew what I wanted to say, but I was more abrupt than I intended. He became defensive, and we both walked away frustrated.

Later that day, I had another difficult conversation. This one went much better. I listened more carefully, chose my words better, and we were able to move forward.

Afterwards, a thought occurred to me: the difference wasn’t just the conversations. I was showing up differently depending on the time of day.

This is a pattern I have noticed in myself over the years. A tough conversation or a challenging task can feel rather different depending on the hour – no matter how rested, prepared or invested I am. At certain times of the day, I feel sharper, steadier and better able to handle thorny issues. At other times, it feels harder to engage or exercise my judgement.

For a long time, I saw this simply as a matter of discipline and willpower. People, including myself, need to perform when required. If a crucial meeting takes place at 8 am, we must deliver our best at 8 am. If feedback needs to be given at 6:30 pm, that’s part of the job – no excuses.

But is it really that straightforward?

As leaders, we spend so much energy deciding what work needs to get done, who should do it and, since the pandemic, where it should be done. But we pay much less attention to the when.

This matters because our cognitive capacity isn’t constant through the day.

It shapes our judgement and capacity for complex thinking, which in turn affects how we perform at work.

So, this week, let’s talk about the implications of circadian rhythms for leadership. How can a sharper awareness of timing help you lead more effectively?

People run on different clocks

You are probably familiar with the related idea of chronotypes. Some people naturally function at their best in the morning, some come alive in the evening, and the rest fall somewhere in between.

What’s interesting is that these chronotypes tend to be quite stable and can’t simply be trained away. Pushing yourself into a 5 am start every day because a book told you successful people wake up early is unlikely to change your personal rhythm. It’ll just mean you spend your peak hours feeling tired and foggy.

Daniel Pink, the author of When: The Scientific Secrets of Perfect Timing, offers a more useful approach: the alignment of type, time and task. The goal isn’t to become a morning person or chase your energy peaks all day long. It’s to become more thoughtful about when you do things. Different types of work make different demands on the brain. Analytical tasks tend to benefit from maximum alertness, while creativity can flourish from the opposite, with a looser, less controlled mental state sparking new insights.

Avoid turning circadian guidance into a set of rigid rules. The more useful takeaway is to match the task to the state of mind it requires, not just to work whenever you happen to have more energy.

Why the clock should matter to leaders

Circadian rhythm usually gets filed under personal productivity or sleep hygiene. But if timing affects how well people think, analyse and communicate, then it should be part of how we organise work. This is where the topic becomes interesting for leaders.

Take the 9 am meeting, for instance. One person arrives already thinking clearly and quickly starts connecting the dots. Another is noticeably quiet for the first half hour. Leaders are likely to interpret these behaviours as important signals. She knows the subject. He is not prepared. She is confident. He lacks presence.

Some of these signals may be accurate. Others may simply reflect chronotype. Most organisations have a built-in bias towards morningness, from the daily review to the assumption that committed employees get to work earlier. That can shape more than meeting dynamics. It can influence who gets seen as sharp, confident or high potential.

Which raises an uncomfortable question for leaders: are we assessing capability, or capability at a particular time of day?

Then there is your own rhythm as a leader. Judgement and emotional regulation decline during circadian lows. This is precisely when decisions falter, conversations go sideways, and negotiations break down. The time of day can even influence how you’re perceived by your team, with research showing ebbs and flows in executive presence and charisma based on a leader’s chronotype.

Finally, it’s worth noting that teams can capitalise on their circadian differences rather than merely tolerate them. Having both morning larks and night owls in the same group allows you to create a natural relay system and extend the workday without placing pressure on any one individual. Projects rarely sit idle and benefit from fresh eyes with every handoff. A shared peak period can be reserved for work that genuinely requires everyone at their sharpest, together.

Working around circadian rhythms

We have spent the last few years redesigning where work happens. Yet while hybrid work has created more flexibility of place, our calendars have often become more crowded and more synchronous.

That creates a contradiction. We now have more freedom than ever to decide when work gets done, but often exercise less control over our own time.

Technology is making another shift possible. Teams can work asynchronously, create shared collaboration windows and organise work around outcomes rather than constant availability. AI adds another layer. As more routine cognitive work gets delegated to machines, human contribution shifts further towards judgement, creativity, persuasion and empathy. That makes it even more important to protect the times when we do those things best.

Here are five suggestions worth considering:

1. Uncover your rhythm.

Circadian-informed leadership starts with the self. Track your personal energy levels for a week. Notice when you do your clearest thinking, when fatigue sets in and when focus returns. Individual patterns are messier and more nuanced than the labels suggest.

2. Audit your calendar.

How are you spending your highest-quality hours? Without circadian awareness, leaders can end up wasting this valuable time on routine tasks like email, while pushing strategic work and tough conversations into whatever slot remains – an expensive habit. Relook at your calendar through the lens of Pink’s advice: match type, time and task.

3. Clock your team.

Learn when your team members are at their peak. Instead of a formal assessment, a direct conversation may be more useful: When do you do your clearest thinking? What meetings would you prefer to have earlier or later? Try to align more demanding work with high-focus periods. Identify overlapping windows for collaborative tasks. Avoid defaulting to a single chronotype when organising the team calendar.

4. Plan for exceptions.

Some things can’t wait for the right hour – an urgent client issue, a board call, a choice that needs to be made asap. Where perfect timing is impossible, you can compensate in other ways. Use a second pair of eyes. Write down decision criteria. Make important handoffs explicit. Avoid making one exhausted person the sole point of approval.

5. Rotate the inconvenience.

In global or distributed teams, some meetings will inevitably fall at awkward times. Avoid making the same people absorb that cost repeatedly. Rotate early and late calls so that no one geography or chronotype is always working against the clock.

An awareness of circadian rhythm allows leaders to view the calendar differently. The goal isn’t to reorganise everything around chronotypes. Rather, it’s to build the habit of stepping back and asking questions like:

• What kind of mental state does this work require?
• Am I assessing capability – or am I assessing capability at a particular time of day?
• When do my team members do their best thinking?
• What’s the most productive time for us to work together?

Today’s leaders are quite adept at matching people, roles and location. Time, too, deserves a place in that equation. Look at what matters most on your schedule this week: the crucial decision, the uncomfortable feedback, the delicate negotiation. As you think through the what, who and where, don’t forget about the when.