I'm currently working through Getting Things Done by David Allen and can recommend it to almost anyone, even if you do not have problems with productivity or organisation as you can get a better understanding of what actually makes you work.
For example I finally found out why I like Evernote: It is a trusted system to just put stuff in, in the jargon of GTD.
I read GTD about four months ago and have started using it at work. It's made an incredible difference by 1) reducing the instances I feel overwhelmed or confused about what to do 2) helping me to better track my primary projects 3) helping me not to forget about small projects or put off the steps to getting them started 4) the system reminds me of what I'm waiting for other people to do, which I never tracked efficiently before.
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