Time blocking
Time blocking is scheduling work as appointments on a calendar, so each piece of work has a time it happens instead of a position in a list.
Time blocking is the practice of giving every piece of work a slot on a calendar. Rather than working from a list and picking whatever looks most urgent, you decide in advance when each thing happens, and the calendar is what you consult during the day. Several named variants sit under it: day theming puts one kind of work on one day of the week, and task batching runs similar work together inside a single block.
The argument for it is that a list is a set of options and a calendar is a set of commitments. A list also hides the arithmetic. Twelve items look like a day until you add up their durations and find fourteen hours of work, which is why the first honest attempt at blocking usually reads as bad news.
Practitioners agree on the failure mode. The plan breaks, often before lunch, because a meeting runs long or something lands. People who keep the habit treat the day plan as something to redo in seconds rather than something to obey, and people who drop it usually drop it after the second or third day that did not survive contact.
The other repeated caution is granularity. Fifteen-minute blocks across a whole day produce a schedule that is technically full and useless, because it prices every interruption at a rewrite. Working versions use blocks of an hour or more, leave real gaps, and have a rule for what gets cut first when the day compresses.
Why it matters
Work with no time on it competes with everything else for the same attention, and what loses is whatever has no deadline. Relationship work is nearly all of that kind, which is why a full week removes it first and why nobody notices until months have gone.