We know day traders who found success by concentrating their attention only on the final 60 minutes or so of each market session. Essentially, they pick out their target stocks early in the day and casually monitor them from 9:30 a.m. until around 3 p.m. ET. Then they really go to work in that final hour and pocket the same profits that other day traders did in 6-1/2 hourssometimes more.

They like the final hour because the market tends to make strong moves heading into the close, and they profitably follow the trend. They prefer the final hour to the opening hour which also produces many strong moves but is so busy and so potentially volatile that the risks are too high for their level of tolerance. Anyone who has been caught in a gap and trap between 9:30 and 10 understands.

There are serious swings during the final hour, but they tend not be as violent as they are at the open. Most important, there are plenty of opportunities to trade.

Why? It can be as simple as workers going to lunch on the West Coast. Remember that 3 p.m. on Wall Street is noon in Los Angeles, San Francisco and Seattle. With a three-hour time delay, people who are just hitting lunch time often run to their telephones and computers to make trades. If you watch the "tape" at that time slot, you will see an increase in activity.

The last half hour of the trading day is the time when the market pros do their best work. Funds that want to buy generally do it during that time slot, and last-minute buy/sell imbalances are straightened out. A significant number of program trades also kick in.

During a down session, there is often a temporary rally when short sellers buy stock to cover their profitable positions. The rally can last until the final bell if the short sellers quickly flip to long positions to take advantage of the upward momentum. On up days there tends to be a stretch of weakness when long players sell stock and take profits. In most cases its a momentary decline and the indexes head back up.

As the market ran toward DOW 10,000 in 2003, we experienced many sessions when the indexes appeared ready to collapse into a long-overdue correction. But in the final hour the unseen hand of the governments plunge protection team apparently appeared to buy boatloads of futures, leading to a surprisingly positive close.

And there are folks like us adding to the momentum. Quite a few traders make their day trades based on only the last 20 minutes. If the market is running into the close, for example, it is a very good bet that the leaders will gap a bit the next morning. Late-day traders buy or go short in the final 20 minutes and sell or cover into that gap with a nice little profit shortly after the opening bell.

During the session, there are signs that point to the direction of the final hour. Market breadth is important. If advancing stocks are far ahead of decliners and many issues are hitting new highs, theres a good chance that any rally will continue into the close. Also important is the put-call ratio. For example, if traders are loading up on call options that increase in value when the underlying stock rises, you can be confident that many individual stocks and the indexes will run in the last 60 minutes.

Keep in mind that final-hour trading is effective during typical market sessions that are dominated by economic reports and the collective action of institutions and individual investors. An outside event like a terrorist threat or natural disaster will roil the markets and make the closing action quite unpredictable.