The one-task rule

Commit to a single task until a natural stopping point before touching another.

Why it works

What people call multitasking is task-switching, and the brain pays a switch cost each time it reconfigures for a new task — slower responses and more errors. Holding one task removes the repeated reconfiguration, so more of your time is spent doing the work rather than re-entering it.

How to do it

1. Choose one task and define its stopping point before you start.
2. Keep every other task out of sight — closed tabs, closed apps, a single document.
3. When a competing task pops up, write it on a capture list instead of switching to it.

Evidence

Task-switching costs (slower and more error-prone performance after a switch) are among the most replicated findings in cognitive psychology across decades of lab studies. (rct)

Lab switch costs are robust; translating exact millisecond costs into total daily productivity loss is an estimate, not a measured constant for your specific work.

Sources

• Rubinstein, Meyer & Evans (2001), executive control of cognitive processes in task switching, J. Experimental Psychology

Common mistake

Believing you are the exception who multitasks well. Self-rated heavy multitaskers tend to perform worse on attention and filtering, not better.