I've been having a bit of trouble with this lately, and I was wondering if anyone had any thoughts on the matter and how to cope with it. I've only been using GTD for a couple of months now so I'm not entirely comfortable with it yet.

I'm a PhD student and while I generally have a lot of work to do, most of it does not have strict deadlines - things will, to some extent, get done when they get done, and my overall goal "get phd" is still 2 years or so off, so doesn't exactly lend itself to motivation!

So, most of my NAs do not have time limits, which suits me quite well. The problem comes when someone else sets me an assignment - for example, at the moment I have some exams to mark which I don't have a deadline for, but I feel I should mark as quickly as possible as otherwise my boss will start bugging me for them. It feels as though I take work set by others to be more important, and I must do it quickly so as to appear efficient, but when it's my own work, I can put it on the backburner. This would be all very well, but the sort of work which gets set by others tends to be things which aren't going to get me a PhD - prepare a general talk on our work, organise a practical class, look up the costs of office supplies etc. A lot of these things need to be done, but they don't normally have to be done now, yet I feel a great deal of time pressure when they are assigned to me.

So my question is really how do you keep your own priorities whilst not ignoring work set by others? Particularly when you're on the bottom rung of the ladder and can't delegate the tasks...