Delegate, Do, Defer, Drop
4D Time Management is a decision framework to triage incoming tasks from "Getting Things Done: The Art of Stress-Free Productivity" by David Allen. Tasks might come from email, chat, phone calls, and other places. Handling the task quickly can help keep focus on priorities and help reduce distractions. They key to effectively handling tasks as they come in is to do, delegate, defer, or drop them.
Do the task right away, then and there, so you no longer have to worry about it. Knocking a task out completely helps minimize cognitive burden.
Delegate tasks that are best left to someone else. If you're worried about the task getting done, you can also defer a task to follow-up later. When delegating, I find it best to delegate urgent tasks synchronously (for example, via a meeting or phone call) and non-urgent tasks asynchronously (for example, via email).
Defer tasks that you need to do, but can wait. If they're time sensitive, schedule them. If they're not time sensitive, then keep them in a running task list. I like to use a bullet journal for this since it handles both.
Drop everything else. This is easier said than done. Dropping tasks often comes with the anxiety of not having enough time, or working on the wrong things. Remember that important tasks tend to persist until they've found their way to you; and when you have too much to do, all you can do is less.
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