Implementation Intentions: Deciding When and Where in Advance
Implementation intentions: A plan in the form "when situation X arises, I will do Y" — deciding in advance exactly when and where a behaviour happens rather than leaving it to the moment.
Where the idea comes from
Peter Gollwitzer introduced the term in the 1990s, distinguishing goal intentions ("I will write more") from implementation intentions ("at 09:30, at my desk, I will write the methods section"). A 2006 meta-analysis with Paschal Sheeran across 94 independent tests reported a medium-to-large effect, d = .65 — the number most articles still quote.
How it shows up
- Genuine intentions that never attach to a moment
- Plans expressed as amounts rather than times: "more exercise", "less scrolling"
- Knowing exactly what you should do and deciding again, badly, every day
What actually helps
- Write the plan as when-and-where, not what: a time, a place, a first action
- Attach it to an existing cue — after coffee, when the laptop opens, on arriving at the desk
- Keep the action small enough that the plan is never unreasonable
- Add a second clause for the obstacle you already know about
Where the popular version overreaches
The famous d = .65 is a 2006 number that the same authors have since walked back. Sheeran, Listrom and Gollwitzer’s 2025 update across 642 tests reports d = .36, finds publication bias at a level they call substantial, and puts the bias-corrected estimate at d = .15 — small by conventional guidelines, though the effect itself remains robust. So this is a real and cheap technique whose size has been oversold, including on most pages that recommend it. It also helps most where the goal is already wanted and the barrier is initiation; for a goal you are ambivalent about, a better plan does not resolve the ambivalence.
Common questions
- Does the if-then format actually matter?
- It appears to. The proposed mechanism is that specifying a cue makes the situation itself trigger the action, rather than requiring you to remember and decide. Vague intentions have nothing to attach to.
- How is this different from a to-do list?
- A list says what. An implementation intention says when and where, which is the part that determines whether it happens.
Sources
Related
- Task initiation
Task initiation is the executive function that gets you from deciding to doing. For a lot of people it is the only part that is broken — and it responds to different tools than focus does.
- Time blocking
Time blocking means assigning specific work to specific hours instead of working from a list. It is effective, and it fails in three predictable ways worth knowing before you start.
- What is body doubling?
- A plain glossary of focus
The vocabulary of attention and procrastination, with sources and honest caveats.
- Executive dysfunction
Executive dysfunction is difficulty with the mental processes that turn intention into action — planning, starting, switching, and holding a goal in mind. Here is what it looks like day to day, and what actually helps.
- Attention residue
Attention residue is the part of your attention that stays behind on the last task after you have moved to the next one. It is why a two-minute interruption costs far more than two minutes.