You can fool some of the people all of the time, the saying goes, and I suppose that's true. But what really interests me is how often we can fool ourselves – why we do it, and why we continue to fall for it.

Time is a currency – one with a very high value, since it comes in limited daily allotments of 24 hours – and how you spend it determines what you accomplish. As I often tell clients, when you say yes to one thing you are saying no to something else, and that means that, for better or worse, your life is defined by the things you say yes to.

Knowing that, you'd think we'd all be at least as disciplined with our time as we are with our money, but the fact is we seem to find ourselves facing the same time deficit, for the same reasons, day after day. Why is that? One social scientist named Jon Elster attributes a lot of the problem to what he calls “the planning fallacy” – the syndrome that causes people to underestimate “the time it will take them to complete a given task, partly because they fail to account for how long it has taken them to accomplish similar projects in the past and partly because they rely on smooth scenarios in which...unforeseen problems never occur.” That's what happens when you find yourself at your desk (again) going through an overflowing inbox (again), bemoaning your shortage of time (again), and telling yourself (again) that you'll catch up with the rest tomorrow. But what makes you think you'll have more time tomorrow? Tomorrow will come with its own imperatives, so anything you don't do today becomes a burden that just compounds.

Let's break out of that cycle once and for all. I suggest doing some “task triage” and assigning all recurring obligations to one of three categories: Things that must be done today, things that should be done this week (which are dealt with during a specially reserved two-hour block of “power time”), and things that can wait or can safely be ignored. And it's important that those things that can wait – the article that looks like it might be interesting, for instance – actually do wait until there is some open time. It's too easy to let those things that are easier, or more enjoyable, sneak into our higher priority time if we let them.

So, no more looking at and paying bills as they come in every day. If it's something you know you need to do regularly, assign it to its slot and do it then. And if you're still feeling time-crunched after trying this exercise, remember there is a fourth category, one that many of you Type-A obsessives tend to forget about: things that can be delegated. If you look down your list of regular time-sucks with an honestly appraising eye, I bet you can find a lot of things you do because you want to, or because you feel you should, but that could in fact be easily managed by someone on your staff.

Trust me, you'll be amazed at how much more in control you feel – and how much more you ultimately get done – when you take this ruthless approach to managing the routine demands on your time. I suggest you try it right now. Or you can put it off until you have more time – but who are you kidding?