Identify and schedule big rocks at the start of each week

On Monday morning (or Sunday evening), name three "big rocks" and block calendar time for each before anything else.

Why it works

A week is the right planning horizon because it accommodates variation in daily energy and commitments while being short enough to stay concrete. By naming and blocking big rocks first, the remaining time absorbs reactive demands rather than reactive demands consuming the entire week. The act of naming makes the intended activities specific enough for implementation intentions to attach to them.

How to do it

1. On Sunday evening or Monday morning, write three things that would make the week successful.
2. Immediately block calendar time for each — treating them as non-negotiable appointments.
3. Fill the remaining calendar with meetings and reactive time only after the rocks are placed.

Evidence

Implementation intention research supports scheduled goal pursuit. Weekly planning studies in organizational settings find that people who plan the week's goals in advance achieve more of them. Vanderkam's related work operationalizes the same mechanism. Gollwitzer & Sheeran's (2006) meta-analysis of 94 studies finds a medium-to-large effect of if-then implementation intentions on goal attainment, and Locke & Latham's (2002) 35-year synthesis establishes that specific, committed goals reliably outperform vague "do your best" intentions — the two mechanisms naming and calendar-blocking a big rock activate. (observational)

The weekly planning research uses varied methods; direct comparison of weekly vs. daily vs. no planning shows weekly planning advantages in some but not all domains.

Sources

• Gollwitzer & Sheeran (2006), implementation intentions meta-analysis, Advances in Experimental Social Psychology
• Gollwitzer, P. M., & Sheeran, P. (2006). Implementation Intentions and Goal Achievement: A Meta-Analysis of Effects and Processes. Advances in Experimental Social Psychology, 38, 69-119.
• Locke, E. A., & Latham, G. P. (2002). Building a practically useful theory of goal setting and task motivation: A 35-year odyssey. American Psychologist, 57(9), 705-717.

Common mistake

Writing the big rocks on a to-do list rather than the calendar — list items do not have a defended time slot and are routinely displaced by whatever is incoming.