NEW YORK — On the eve of his last publishing convention as head of the Time Warner Book Group, Laurence J. Kirshbaum looks back at more than 30 years of such gatherings and remembers a calmer, clubbier time.

"When I started out, most of the conventions took place in hotel suites, where every publisher would entertain the booksellers at cocktail parties. There was none of the Hollywood hoopla we have now," says Kirshbaum, who is among the thousands expected at this weekend's BookExpo America, to be held at New York's Jacob K. Javits Convention Center.

"It was really a kind of floating party from suite to suite among people who were friends. It was a much more collegial business, without the pressure everyone has now from being with a publicly held company."

The good news, he says, is that everything got big. The bad news, too, is that everything got big. Kirshbaum, who hopes to become a literary agent after retiring from Time Warner at the end of the year, has watched the convention and his company expand, transform and survive.

Kirshbaum, 61, started out with Warner Books in the 1970s, when it was "essentially a pulp-fiction house." Over time, Warner Books has grown into a $500 million corporate colossus, with authors ranging from James Patterson to J.D. Salinger. It has merged with Time Inc., merged and unmerged with AOL and endured rumors of a buyout by Random House.

Meanwhile, BookExpo America, once called the American Booksellers Association Convention, managed a near-fatal feud between publishers and independent retailers in the mid-1990s, largely over the rise of superstores. It now mirrors the sprawling, contradictory nature of the industry itself.

At BookExpo, blockbusters such as "Harry Potter and the Half-Blood Prince" will be hyped alongside literary releases by Umberto Eco and E.L. Doctorow and scholarly works by university presses. On a given day this weekend, one might attend an author luncheon sponsored by independent booksellers, sit in on a discussion about the next generation of editors, then stand in line to meet Wynonna Judd.

Industry officials debate the necessity of BookExpo America, but Kirshbaum is among the believers, hoopla and all. He has good reason. Last year's convention greatly helped two of Time Warner's biggest recent best sellers: Malcolm Gladwell's "Blink" and Jon Stewart's "America (The Book)." This year, Time Warner author Billy Crystal, who has a memoir coming out, will officially open the convention Thursday night. The convention runs to Sunday.

"It's still a way to break books out," Kirshbaum says. "Publishers and booksellers love to think about what's going to work and what are the holy grails for the year."

"There's a lot of schmoozing going on, but real work gets done and you can really set up books coming down the pike," says Suzanne Herz, a publisher at Doubleday, which this year will feature a new novel by Myla Goldberg, "Wickett's Remedy."

BEA is big, but it has been bigger. Because of consolidation among publishers and booksellers, show manager Chris McCabe expects this year's convention to occupy about 270,000 square feet of floor space, some 50,000 square feet less than it did in the late 1990s.

The industry itself has never been bigger — a record 195,000 new books came out last year, according to a preliminary report from the research organization R.R. Bowker — but it has been stronger. The Book Industry Study Group estimates a drop of 40 million in the number of the books sold in 2004. Rising prices have kept dollar sales up, with revenues estimated at more than $28 billion last year, but have also made used books a hot market, especially among students.

Beyond sales, the market seems to be changing. According to the Bowker study, a "seismic shift" is under way "from the political to the personal," as readers turn away from topical works after two close presidential elections, the Sept. 11 terrorist attacks and the Iraq war.

Politics was king at last year's BEA, starting with keynote speaker Bill Clinton. This weekend, however, the power should be spread around, with featured authors including novelists John Irving and Michael Cunningham, historian Doris Kearns Goodwin and television journalist Mike Wallace.

"Last year was probably atypical; I don't think you'll have that kind of political undercurrent this time," says Mitchell Kaplan, president of the American Booksellers Association.

"There's always been a diversity in what we've sold, and this year people will probably be reminded of that."

Retiring head of Time Warner Book Group