It took Welsh a year to write Glue — a lifetime by his standards — and he admits that he still feels “insecure” about it. “It’s the biggest thing I’ve ever done,” he says. “These different times and these four different voices. They’ve got to be the same person as a 15-year-old and a 25-year-old and a 35-year-old; they’ve got to be the same character. You’ve got to make sure that what you’re doing is consistent, you know, all these horrible housekeeping details.”

But then Welsh has always seemed more at ease composing rollicking set pieces than finely woven tapestries. And while he has a keen sense for emotional truths, he is not what you’d call a novelist of ideas. “Other people’s views,” he says, “are much more interesting than mine.” In Glue, though, Welsh found himself having ideas thrust upon him. “It became a social-history type of a book in a way,” he says. “I didn’t mean it to be, but I got more into looking at that, the changes, the things that people from that social class go through. So there were a lot more social issues in it than I would normally have.”

This being Welsh, the most intriguing social issue in Glue arises as a sort of joke. Toward the end of the book, the self-styled lady’s man Terry — unemployed, living at home with his ma, getting increasingly podgy and unattractive — reacts with jealous rage when one of the younger neighborhood boys has the gall to enroll in college: “In the District Court of his mind where Rab Birrell is on trial charged with being a poncy student cunt, Terry is assembling an absolute fucking welter of evidence.”

This is a funny line, but it also marks the most sinister force at work in Glue: working-class rivalry, the bitterness and dissatisfaction that make people resent a neighbor’s new car, new career, or even new curtains. It’s a central, shoddy truth of the British working classes: the forces that keep poor people down come from below as often as they do from above. The theme of jealousy and rivalry runs throughout the book, and it provides some of its most heartbreaking moments. Welsh, meanwhile, says he hit on the idea “inadvertently.”

Welsh has always been almost pathologically modest about his work. When asked what he likes most about Glue, he responds, “Just the fact that it’s finished, that I don’t have to look at it any more.” Throughout his rise to fame, Welsh has aggressively avoided even the appearance of pretension. “It’s not like I hang out at the Groucho Club,” he says, referring to the trendy London literary salon. “It’s not like I hang out with all these writer types. Most of the people I hang out with are clubber types, musicians, people who go to the football.”

And, although Welsh lives in London these days, he still goes up to Scotland “at least once a month” to hang out with his friends, his boozy muses. “We’ve been mates for years, some of them 30 years,” he says. “We still all hang out.” Then he points to the dedication page, the names — Deano, Scrap, Jimmy, Tam — of the men who served as inspiration for his book. You wonder whether there might not be a Terry or two among them. Irvine, Irvine, sitting in a tree, o-r-a-t-i-n-g.

“I think for a while a lot of pals up there were quite, kind of, ehm, probably a bit keen to slap me down,” Welsh says. “They were worried I was going to become this arrogant bastard, you know, but I’m no more arrogant than I ever was. I was always a bit like that. Most of them will tell you that I haven’t really changed. I’m just one of the boys.”

But the boys are growing up, and so is Welsh. Does he see a day when he might move on to new pastures, perhaps write a novel about, say, London? “I have so many stories in my head related to where I come from,” he says, a little grumpily. “I want to exhaust these before I move on.” And then he tells a story, with as close to a smile as Irvine Welsh gets, about how he recently got involved with a project — for the children’s charity UNICEF — that entailed writing a novella based in Sudan. Apparently, he had a terrible time of it. “There were no drugs,” he says, shaking his head, “no housing estates.”

Chris Wright can be reached at cwright[a]phx.com.

Listen to an excerpt from Chris Wright’s interview with Irvine Welsh and see how well you understand Welsh's brogue! Click here: http://mp3.thephoenix.com/mp3/IrvineWelsh.mp3.