TL;DR: Getting Things Done is five habits: capture everything, decide what each thing needs, organise it into projects and next actions, review it weekly, and do the work. A task tree suits it well. Projects become parent tasks, next actions become the subtasks at the edge of each branch, contexts become tags, and the weekly review becomes a repeating task.
David Allen's Getting Things Done came out in 2001 and is still the most influential personal productivity system around. Plenty of people have read it, set it up over a weekend, and abandoned it a month later. Usually that's because the setup got too complicated, not because the ideas were wrong.
This post explains GTD in plain terms and shows a lightweight way to run it on a nested to-do list, with as little structure as possible.
GTD in five steps
1. Capture
Write down everything that has your attention. Work projects, errands, ideas, worries, things you've promised people. Allen calls it "getting it out of your head". The aim is a mind that isn't spending energy trying to remember things.
You need one place where everything lands first: an inbox. In a to-do app, that can be your top-level list or a task called "Inbox".
2. Clarify
Go through the inbox one item at a time and ask: is it actionable?
- No: delete it, file it as reference, or park it in a "Someday" list.
- Yes, and it takes under two minutes: do it now.
- Yes, and it needs one step: it's a next action. Write it as a verb.
- Yes, and it needs more than one step: it's a project. Decide the very next action.
The two-minute rule alone is worth the book. Tracking a quick task takes longer than doing it.
3. Organise
Allen's lists are:
- Projects: any outcome needing more than one step.
- Next actions, grouped by context: where or with what you can do them (calls, at the computer, errands, at home).
- Waiting for: things you've handed to someone else.
- Calendar: things that must happen on a specific day.
- Someday/maybe: things you might do but aren't committed to.
4. Reflect
Once a week, review everything: empty the inbox, check every project has a next action, look at your calendar, and update the waiting list. Allen calls this the weekly review and says it's what keeps the system trustworthy. In our experience he's right. See how to do a weekly review for a twenty-minute version.
5. Engage
Do the work. When you have time, pick from the next actions that fit your context, the time available and your energy.
Why a tree fits GTD
The awkward part of GTD in most apps is keeping projects and next actions connected. Many setups have a project list in one place and next actions in another, linked only by name. When you finish a next action, you have to go and find the project to decide what's next.
In a task tree, a project is a task with children, and its next actions sit inside it. Finishing one leaves you looking at the rest. And because the tree can go as deep as needed, big projects can have sub-projects without needing a separate system. Allen's "natural planning" (purpose, outcome, brainstorm, organise, next actions) maps straight onto a branch.
A lightweight GTD setup on a task tree
Here's a setup that uses nothing more than nested tasks, tags, dates and a short daily list. It works in Tatask, and in any app with the same building blocks.
Top level
Keep the top level short:
- Inbox: capture here. Clarify it daily or every few days.
- One task per area or big project: "Work", "Home", "Move house", "Side project".
- Someday: anything you're not committed to yet.
Projects and next actions
Inside each area, every project is a task. Inside each project, its steps. The next action is simply the first unfinished step on each branch, so you don't need a separate next-actions list. If the next step is vague, break it down until it isn't.
Contexts as tags
Put a tag in each next action for where you can do it:
#calls#computer#errands#home#waitingfor things you're waiting on someone else for
When you're at the shops, open #errands and see everything from every project you can do there. That's exactly what Allen's context lists are for, without maintaining separate lists. More on this in tags vs folders and on the tags feature page.
Calendar items as dates
Anything that must happen on a particular day gets a due date. Allen is strict that the calendar is only for things that genuinely must happen that day, and that's good advice. Don't put dates on things you'd merely like to do on a day; that's what the daily list is for.
Today
Allen doesn't prescribe a daily list, but most people find one helps. Each morning (or the evening before), choose a handful of next actions and star them so they show up in Today. It's a bridge between the full system and what you'll actually do.
The weekly review as a repeating task
Make "Weekly review" a task that repeats every Friday. It'll come back on its own, and you can keep the checklist as its subtasks.
Where people go wrong with GTD
Too many contexts
Allen's examples include a dozen contexts. Most people need four or five. If a tag view is never opened, delete the tag.
Treating every idea as a project
Not everything you write down needs a project. If you're not committed, it goes in Someday. Reviewing Someday monthly is plenty.
Skipping the weekly review
This is the one that kills most GTD setups. Without the review, inboxes overflow, projects lose their next actions, and you stop trusting the lists. Twenty minutes a week is the cost of keeping the system honest.
Perfecting the system instead of using it
GTD rewards tinkering, which is dangerous. If you've spent more time setting up than doing, simplify. A rough system you use beats a beautiful one you don't.
Is GTD right for you?
GTD suits people with a lot going on across several areas who want to feel sure nothing has been forgotten. It's more setup than simpler methods like the Ivy Lee method, but it catches more.
If you mainly struggle with one important task each day, Eat the Frog is lighter. If urgent things keep crowding out important ones, try the Eisenhower matrix. For organising notes and reference material alongside tasks, the PARA method pairs well with GTD.
Not sure? My two-minute planning method quiz suggests a starting point.
Start small
You don't need the full system on day one. Try this for a week:
- Capture everything into one inbox.
- Clarify it once a day using the two-minute rule.
- Make sure each project has a clear next action.
- Do a weekly review on Friday.
Add contexts and Someday lists once the basics are habits. The parts that stick are the parts worth keeping.
Frequently asked questions
What are the five steps of GTD?
Capture everything that has your attention, clarify what each item means and what the next action is, organise the results into lists, reflect on them in a weekly review, and engage by doing the work.
What is a "next action" in GTD?
The very next physical, visible thing you'd do to move something forward. "Call the garage to book the MOT" is a next action; "car" is not.
Do I need special software for GTD?
No. GTD was designed to work on paper. Any app that lets you keep projects, next actions and contexts apart will do.
What's the two-minute rule?
If an item will take less than two minutes, do it as soon as you clarify it, rather than writing it down. Tracking it would take longer than doing it.
How do GTD contexts work in a tag-based app?
Use a tag per context, such as #calls, #computer or #errands. When you're in that context, open the tag's view to see everything you can do there.