CBS declared the summer rerun season over in mid-August. But NBC said the fall season didn't start until last week, the day after its Athens Olympics coverage concluded. Fox, on the other hand, said its new season began in early June because television is a year-round business. ABC isn't committing (not surprising, given that ABC suits know a low profile can buy them an extra year or two in their jobs before the Big Cheeses at parent Disney cut off their heads to serve angry shareholders).

Is it any wonder viewers have been confused and anxious, not knowing when they need to return to their TV sets in earnest?

We're here to help.

Nielsen has declared Sept. 20 to be the official start of the 2004-05 television season. And believe it or not, each of the broadcast networks signed off on that.

"The networks sit down in the spring, and generally they will agree on a start date," Nielsen spokesman Jack Loftus explained, though he acknowledged that sometimes there is discord.

"Traditionally, it's roughly the third Monday in September," he added.

There have been notable exceptions in recent years. In 2000, the start of the season was pushed back to Oct. 2 because the other networks did not want to let NBC include in its season average its coverage of the Summer Olympics from Sydney, which ran from Sept. 15 to Oct. 1.

(Ironically, given how poorly those Olympics did for NBC, it was hardly worth the argument.)

More recently, the networks agreed to delay the start of the 2001-02 season by a week when they dumped their lineups and all their ad breaks -- including promos for new series debuts -- for days after the Sept. 11 attacks on the World Trade Center and the Pentagon.

The start of the season has not always been Nielsen's decision. For years, right up to the early '90s, a reporter named Bob Knight, who covered the television industry for the trade paper Variety, made the call.

Loftus, who was Knight's editor at Variety in the '80s, says he does not know how Knight became the last word on the subject.

"It was a lot of phone calls and, 'Okay, Variety is going to announce the start on that date' and . . . Nielsen wasn't really a part of it.

"He was the guru. I remember sitting there at my desk and saying, 'Bob, when are you going to start the TV season?' And I'd say, 'How firm is that?' And we would build a New Season Start section in the paper."

But here's a little-known fact: Knight is not the only reporter who got to determine a season's official launch date. For one brief shining moment, in 1992, that responsibility fell to Brian Lowry, then a twentysomething rookie TV reporter at Variety. Knight had left the paper, and the networks were having trouble agreeing on a date.

"Bob Wright, head of PR at ABC, called and said, 'When does the season start?' " Lowry recalled. "I said, 'How the hell do I know?'

"He said, 'Because Variety sets the season and Bob Knight is not around anymore.' . . . That was the first I'd heard of it," Lowry said.

"The funny part was, Bob was an institution and in his late sixties; I was in my twenties. It seemed like a peculiar way to settle things."

Lowry, now a columnist and the TV critic at Variety, still gets a chuckle out of it. "It was kind of like 'Lord of the Rings,' because I'm sitting there minding my own business and they call and say, 'Little Frodo, you're the key to everything.' And I was, like, 'What do I have to do with it?' "

According to Lowry, CBS had the Summer Olympics that year and wanted to start the season earlier, on Sept. 14; the other networks insisted on Sept. 21.

"I said the 21st," Lowry said. "After that it didn't come up again for several years. The next time it came up, Nielsen actually agreed to set the date. Nielsen was always in a position where they did not want to set it because they did not want to play favorites with one client over another.

"For whatever reason, they changed that policy and said, 'We will determine it after having talked to clients.'

"Either that or I did a really crappy job."