Minds wander in nearly half of waking moments, according to a 2010 Harvard study that used an iPhone app to ask 2,250 adults, at random times, what they were doing and thinking. In 46.9 percent of replies, people were thinking about something other than their current activity, and minds wandered often whatever the activity was. The volunteers were self-selected app users, most of them in the US.¹

Concentration is less a state you reach than a return you keep making. Of the techniques in this guide, the one with the most experiments behind it is a plan made in advance. A 2025 meta-analysis of 642 experimental tests, mostly with adults, found that if-then plans reliably help people act on their goals, although the authors judge the average benefit small once publication bias is taken into account.²

How to focus, in short: decide in advance what you will work on and how you will handle distraction, cut the interruptions you control, and use breaks to restore energy. The six steps, roughly in order of how strongly the evidence backs them as focus aids:

1. Pick one task and plan when and where you will start it
2. Decide now what you will do when distraction strikes
3. Silence or batch notifications and move the phone out of sight
4. Check email and chat at set times
5. Note where you stopped before you switch
6. Take short breaks, and longer ones after hard thinking

Attention drifts, and many interruptions start with you

Focus slips from the inside as well as the outside. In a 2005 study, Gloria Mark and colleagues at the University of California, Irvine shadowed 24 employees of an IT and accounting services firm for about three days each: people spent about 11 minutes on one piece of work before switching or being interrupted, and 52 percent of interruptions were self-started.³

Many self-interruptions are ordinary pauses: in the same study, most were for personal matters such as breaks, while outside interruptions most often concerned people’s main work.³ Part of the fix, then, is a plan for your own attention, and part is a barrier against other people’s claims on it.

What does not hold up well is the popular idea that self-control runs on a fuel that each hard task burns.

Myth

Self-control is a limited fuel: every hard task you finish leaves less for the next one.

Fact

In a preregistered 2021 test in 36 labs with 3,531 people, a demanding self-control task did not clearly weaken self-control on the task that followed.

That 2021 test did find two hints: a very small effect when excluded participants were added back, and a larger one among people who said they felt more tired, both from exploratory analyses.⁴ So feeling tired may matter even if a simple fuel-tank model does not hold.

How to focus, step by step

How to focus comes down to six habits, and the evidence for them as focus aids weakens down the list. The first two draw on the 2025 meta-analysis of planning experiments, the next three mainly on smaller experiments, several lasting only a week or two, and the last on a review that found breaks restore energy more reliably than they improve performance.

1. Pick one task and plan when and where you will start it

Choose the task that matters most today, then tie its start to a specific moment with an if-then plan, which researchers call an implementation intention: “If it is 8 a.m. and I am in my office, then I open the client proposal.” In the 2025 meta-analysis, plans in this if-then form had larger effects than plain schedules, and plans naming both a time and a place had larger effects than plans naming a time alone.²

The study

Moderate evidence

Do if-then plans work? Sheeran, Listrom and Gollwitzer, 2025

Paschal Sheeran of the University of North Carolina, Olivia Listrom and Peter Gollwitzer, whose work introduced if-then plans, pooled experiments comparing people who made such plans with people who did not. Planning helped with behavior, emotions and thinking tasks, including tests of attention and memory. Small studies with positive results were overrepresented, and after correcting for that, the authors judged the average benefit small.²

For focus at work, the evidence is thinner than the headline. Effects in field studies were about half the size of those in the lab, tests with workplace samples showed a small effect, and only three tests measured concentration itself. Comparing across studies, plans also had larger effects when people rehearsed them at least once, with no added benefit from more repetitions, and smaller effects when they also spelled out how or for how long they would act.²

2. Decide now what you will do when distraction strikes

The “if” in a plan can be an obstacle rather than a time. In the same meta-analysis, plans whose “then” was to ignore something, such as an unwanted thought or a distracting sight or sound, helped across 38 tests. The authors also describe a 2010 experiment in which people doing a concentration test while hearing stigmatizing comments about appearance could not shut them out when simply told to ignore them, but scored as well as an undisturbed group when they had planned, in if-then form, to ignore the comments.²

1. Start plan: a time and a place in the “if”, the first action in the “then”
2. Distraction plan: the likeliest distraction in the “if”, a quick response, such as ignoring it, in the “then”

Pick the distraction most likely to break your focus, and give it a response you can carry out in seconds.

3. Silence or batch notifications and move the phone out of sight

Fewer alerts and a phone out of sight made students feel slightly more attentive in a 2016 experiment with 221 University of British Columbia undergraduates. After a week with alerts off and phones stowed, they rated their inattention slightly lower than after a week with alerts on and phones within reach, 2.27 versus 2.38 on a 1-to-4 scale, but reported no clear change in productivity; they knew which week was which, and every measure was self-reported.⁵

Switching everything off is not the only option. In a 2019 experiment with 237 smartphone users in India, most of them employed and recruited online, people whose notifications arrived in three daily batches rated themselves more attentive than people who got alerts as usual, while those who got none felt more anxious and no more attentive. The app was built for the study by a company whose staff co-wrote the paper and was not for sale, and nearly a third of those who started did not finish.⁶

Moving the phone out of sight may also help, though the evidence is weak and two 2024 meta-analyses disagree. One found that a phone’s mere presence hurt working memory but had no clear effect on the other mental skills tested, and its author judged the evidence limited.⁷ The other, pooling 33 studies with 4,368 participants, found no clear effect on thinking overall, although it did not test skills such as working memory separately.⁸ In practice, turn off the alerts you do not need during focus time, let the rest arrive in a few batches if your phone allows it, and put the phone in a bag or drawer.

4. Check email and chat at set times

Checking email three times a day lowered daily stress in a 2015 experiment by Kostadin Kushlev and Elizabeth Dunn of the University of British Columbia. Its 124 adults spent one week checking email three times a day with alerts off and another checking as often as they could. They checked about 5 times a day instead of about 13, felt less stressed and felt less distracted by email, although that last effect held for the students in the sample, not for the third who were working community members. The authors caution that, because they measured many outcomes, even the stress result could be a chance finding.⁹

The authors suggest the benefits may go further when a whole team or company changes its expectations about replies.⁹ For managers, that points to agreeing team norms early, including how quickly messages need an answer.

5. Note where you stopped before you switch

When you must leave a task unfinished and expect to be pressed for time when you return, a brief plan for coming back can help you settle into the next one. In a 2018 paper reporting four studies, Sophie Leroy and Theresa Glomb found that when people expected to be short of time on returning to an interrupted task, briefly planning their return reduced attention residue, the pull of the task left behind, and their performance on the interrupting task did not suffer.¹⁰ Two lines will do: where you stopped, and the first thing you will do when you return.

6. Take short breaks, and longer ones after hard thinking

Short breaks restore energy more reliably than performance. A 2022 meta-analysis of 22 study samples with 2,335 people found that breaks of 10 minutes or less modestly raised vigor and reduced fatigue, but did not clearly improve performance overall and showed no clear benefit after cognitively demanding tasks. Longer breaks were linked to larger performance gains, and the authors suggest that recovering from draining work may take more than 10 minutes.¹¹

WiserHours

Before your next focus block

• One task chosen, with an if-then plan for when and where to start
• A second if-then plan for the likeliest distraction
• Alerts you do not need off or batched; phone in a bag or drawer
• Email and chat closed until the next set check
• A two-line note ready for any forced switch
• A break planned, longer after hard thinking

Find this checklist online:
https://wiserhours.com/focus/how-to-focus/#checklist-how-to-focus-steps

Sleep, caffeine and exercise also shape focus

In lab studies, going a night without sleep hurts simple attention and vigilance more than other thinking skills. A 2010 meta-analysis of 70 articles by Julian Lim and David Dinges of the University of Pennsylvania found that 24 to 48 hours without sleep had its largest effects on simple attention and vigilance, and no clear effect on reasoning accuracy. The studies were short lab experiments with about 21 people each on average, so they show what a lost night does, not what months of short nights do.¹² If short nights are the issue, habits that help busy adults sleep better are the practical place to start.

Caffeine raises alertness in moderate doses, according to the EU’s European Food Safety Authority (EFSA), whose 2015 safety review found no concerns for healthy adults from single doses up to 200 mg or daily intakes up to 400 mg. These are safety ceilings, not advice to take caffeine. EFSA gives a lower figure for pregnant and breastfeeding women (up to 200 mg a day raised no concerns for the fetus) and weight-based limits for children and teenagers, and found that 100 mg may disturb sleep in some adults, especially near bedtime. Its figures do not cover people with medical conditions or those taking medicines; a doctor or pharmacist can say what applies to them.¹³

A single bout of exercise gives thinking a small, temporary lift. The scientific review behind the 2018 US Physical Activity Guidelines rated as strong the evidence that a bout of moderate-to-vigorous activity improves cognition for a while afterward, with the most consistent effects on executive function, and smaller effects in young adults than in children and older adults.¹⁴

Further reading

• 

  Rethinking Positive Thinking: Inside the New Science of Motivation

  by Gabriele Oettingen

  Oettingen explains WOOP, which pairs picturing an obstacle with an if-then plan, the planning method this guide ranks first.

As an Amazon Associate WiserHours earns from qualifying purchases.

Which focus techniques have the best evidence?

If-then planning has the largest body of experimental evidence of the techniques in this guide; several of the others rest on single experiments lasting a week or two, often with students, and brain-training games show little evidence of everyday benefit.

When trouble concentrating needs a doctor

Trouble concentrating can be a sign of depression, anxiety, sleep apnea or ADHD, among other causes, according to the US National Institute of Mental Health (NIMH), the UK’s NHS and the US National Heart, Lung, and Blood Institute (NHLBI), and sudden confusion is a medical emergency. The tiers below are our own ordering of their advice; outside the UK and US, read GP or provider as your family doctor.

• Now: if you or someone with you suddenly becomes confused, the NHS says to go to A&E (the emergency department) or call 999 in the UK, and not to drive yourself there; elsewhere, call your local emergency number.¹⁶ If trouble concentrating comes with thoughts of suicide or self-harm, call or text the 988 Suicide & Crisis Lifeline in the US, as NIMH advises (911 if a life is in danger), or your local emergency number elsewhere.¹⁷
• Soon: NIMH lists difficulty concentrating among the common signs of depression, a diagnosis that requires symptoms most of the day, nearly every day, for at least 2 weeks, and advises talking to a health care provider if signs persist.¹⁷ Worry that is hard to control and affects daily life is the main symptom of generalized anxiety disorder, which can also make it difficult to concentrate; the NHS advises seeing a GP if you think you might have it.¹⁸ Loud, frequent snoring, gasping for air during sleep and daytime sleepiness that can make it hard to focus are symptoms of sleep apnea to raise with a provider, the NHLBI says.¹⁹
• At your next appointment: if you are often easily distracted, forgetful or struggle to finish tasks, and it affects work or relationships, the NHS suggests seeing a GP about ADHD. It notes that symptoms usually start before age 12 and that a GP may also consider other causes, such as anxiety.²⁰

The bottom line

The best-tested way to focus is to decide before you start: which task, when and where you will begin it, and how you will ignore the likeliest distraction. Then cut the interruptions you control, with alerts batched or off and email checked at set times, and use breaks to restore energy rather than expecting them to sharpen hard thinking. If poor concentration persists with low mood, constant worry, loud snoring or daytime sleepiness, NIMH, the NHS and the NHLBI advise seeing a doctor; sudden confusion is an emergency.