Since the early work of Halberg(1960), the existence of human "circadian rhythms" has been well-known to biologists and psychologists. Circadian rhythms dictate that there are certain times of the day when we are at our best both physically and psychologically. At its simplest, the majority of us feel more alive and creative in the mornings, while come the evenings we are fit only for collapsing with a good book or in front of the television. Other of us note that in the morning we take a great deal of time to get going physically and mentally, but by the evening are full of energy and bright ideas, while a very few of us feel most alert and vigorous in the late afternoon. Irrespective of our personal rhythms, most of us have a productive period between 10:00 a. m. and noon, when the stomach, pancreas, spleen and heart all appear to be in their most active phases. Conversely, the majority of us experience a low period in the hour or two after lunch(a time when people in some societies sensibly take a rest), as most of our energy is devoted to the process of digestion. The. simple rules here are; don't waste too much prime time having a coffee break around 11:00 a. m. when you should be doing some of your best work, and don't make the after-lunch period even less productive by overloading your digestion. A short coffee or tea break is, in fact, best taken on arrival at the office, when it helps us start the day in a positive mood, rather than mid-morning when it interrupts the flow of our activities. Lunch is best taken early, when we are just beginning to feel hungry, and we are likely to eat less than if we leave it until later. An early lunch also means that we can get back into our productive stride earlier in the afternoon. Changes in one's attitude can also enhance personal time management. For example, the notion of pro-action is eminently preferable to reaction. To pro-act means to anticipate events and be in a position to take appropriate action as soon as the right moment arrives. To react, on the other hand, means to have little anticipation and do something only when events force you to do so. Pro-actors tend to be the people who are always one step ahead of other people, who always seem to be in the right place at the right time, and who are always better informed than anyone else. Many of us like an easy life, and so we tend to be reactors. This means, that we aren't alert to the challenges and opportunities coming our way, with the consequence that challenges bother us or opportunities pass us by before we're even properly aware they're upon us. We can train ourselves in pro-action by regularly taking the time to sit down and appraise the likely immediate future, just as we sit down and review the immediate past. Psychologists recognize that we differ in the way in which we characteristically attribute responsibility for the various things that happen to us in life. One of the ways in which we do this is known as locus of control(Weiner, 1979), which refers to assigning responsibility. At its simplest, some individuals have a predominantly external locus of control, attributing responsibility to outside causes(for example, the faults of others or the help given by them), while with other individuals the locus of control is predominantly internal, in which responsibility is attributed to oneself(for example, one's own abilities or lack of them, hard work, etc). However, the picture usually isn't as simple as this. Many people's locus of control is more likely to be specific to a particular situation, for example internal in certain areas, such as their social lives, and external in others, such as their working lives. Or, to take another example, they may attribute certain kinds of results to themselves, such as their successes, and certain kinds of results to other people, such as their failures. Obviously the best kind of locus of control is one that is realistic and able to attribute every effect to its appropriate cause, and this is particularly important when it comes to time management. Certainly, there are occasions when other people are more responsible for our time loss than we are, but for most of us, and for most of the time, the blame must fall fairly and squarely upon ourselves.