Every employee has certain obligations throughout the workweek on top of their core job: like attending meetings, taking phone calls, replying to email, and filling out paperwork. It's natural to want to tackle these things as they come up. But your core job requires solid blocks of time, when you can dive in, get creative, and think things through without interruptions.
When you've got a 10 a.m. meeting, a 1 p.m. lunch, and a 3:30 phone conference, your core work time gets fragmented into small chunks sandwiched between those obligations. A schedule fragmented by appointments means that you won't start that big project just now, because you've got a meeting in 25 minutes.
One of the more advanced (and obvious!) productivity techniques is to group similar to-do's and knock them all out at the same time. I call this task batching. It makes better use of your day by chunking similar activities into contiguous blocks of time.
You don't do laundry every time you throw a shirt into the hamper—you wait till you've got a full load to run. That's task batching. There are two ways to batch tasks: by action and by context.
To batch tasks by action, save up similar to-do's and set aside time to get them all done at once. This works especially well for repetitive tasks. For example, a freelancer I know gets requests for phone consultations by potential clients throughout the week. To avoid fragmenting his days with one phone call here and one phone call there, he blocks out Tuesday and Thursday mornings exclusively for these calls. That way he can easily get into and stay in client discussion mode. Having a set time helps reduce scheduling back-and-forth too: when someone asks to schedule an initial consultation by phone, he says "Pick any time between 10 a.m. and noon on any Tuesday or Thursday."
This same principle works for clearing out your email inbox. Set times every day, like at 11 a.m. and 4 p.m., to process your mail. Then shut down your email program the rest of the time to work without the distraction of that "new mail" alarm going off.
To batch tasks by context, group the things you have to do by situation, surroundings, or the tools you have available. For example, keep a "to call" list on your cell phone. You can also keep a grocery list on your phone. Keep all the paperwork you need to file or discard near the filing cabinet, with folders, a label maker, and a shredder nearby. And before you leave work, collect paperwork you have to review into a folder that lives in your workbag, for easy access on the train or bus ride home. Productivity expert David Allen recommends including context with every task on your to-do list, like "Calls," "At Computer," "Errands," "At Office," "At Home," etc.
The goal of task batching is to give yourself as much uninterrupted time to do your core work as possible in between meetings, phone calls, and email. When you can, top- or bottom-load your schedule, stacking meetings one after another at the beginning or end of the day, to reduce schedule fragmentation.
Task batching defragments your calendar and helps you take advantage of momentum to get done things more efficiently than switching between one-off to-do's.