The decision

This chapter asks you to decide something. It comes late because at the start it would have sounded like being told to concentrate, which you've heard since school. By now you've seen that you were never doing several things at once, only switching. You've seen that each switch costs a restart and a period of divided attention, and that the feeling of a busy day says little about what got done. You've also seen that a half-done task pays nothing and still takes up room in your head, and that a good share of the switches are yours, made at the moment a task gets hard.

Here's the rule I'd suggest. Put it in your own words if you like.

I pick one thing, I work on it until a stopping point I've named, and I write a parking note before I touch anything else.

It has five parts, and each answers a chapter.

I choose on purpose. Each morning I write down what's open, pick by consequence, and give the first stretch to the task that needs the most thought.

I keep no more than three things open. A fourth waits until one is finished or dropped.

I work in stretches with a named end. The inbox is closed and the phone is away. Stray thoughts go on the capture sheet.

Messages get their own stretches. I deal with them in batches at set times. People know to ring if it's urgent.

Nothing gets left without a note. Whenever I stop, I write where I am and what's next. At the end of the day I write down what I finished.

It helps to plan for the moments when the habit will try to restart. Peter Gollwitzer and Paschal Sheeran pooled ninety-four tests of plans in the form "when X happens, I'll do Y" and found that they make people more likely to follow through. A plan like this works because you've decided what to do before the difficult moment comes. Three are worth writing down.

When I think of another task in the middle of a stretch, I'll write three words on the capture sheet and carry on.

When I get stuck and feel the pull to check something, I'll stay five more minutes and write a bad version of the next sentence.

When someone interrupts me, I'll write my parking note before I turn to them.

I'll be honest about what to expect, and this is my expectation and not a finding. The first week will feel slow and slightly irresponsible. You'll be sure that disasters are piling up in your closed inbox, and when you open it you'll find they mostly weren't. One or two people may remark that you took an hour to reply. Your finished list will start short and get longer. The pull to switch will be strong for some days and then fade, though it won't disappear. You'll still have fragmented days, because some days are like that. What should change is that the important thing moves forward every day. You should leave with fewer things open than you arrived with, and the tiredness at ten past five should be the kind that comes with having finished something.