He doesn't look like a relationship guru. The spiky bleached hair. The little hoop earring in each lobe. The tattoos, two per upper arm, another hidden on his back. Alavender plastic child's bracelet made of dog bone and heart shapes strung together by his four-year-old daughter circles his wrist.

The hefty silver chain draped from a front belt loop to the wallet in his rear pocket slaps his backside as he makes his way through the men's department on the second floor of Barneys. When Greg Behrendt walks, the vertical action is equal to the lateral move: He bounces. Viewing him from behind, you see a black T-shirt, long olive drab cargo shorts, white socks, and black high-top Converses bobbing between the store's suspended mannequins. If you didn't know better, you'd think Bart Simpson had assumed a third dimension. How, you wonder instead, did a ten-year-old get so big?

Behrendt is the best-selling coauthor of He's Just Not That into You, a hilarious self-help manual about recognizing and exiting ambiguous--or just plain bad--relationships. Thanks to its pop-but-sage insider advice and several appearances on Oprah, Behrendt is poised to become a TV star. This season he’ll be hosting two shows on relationship maintenance: The Greg Behrendt Show, a syndicated weekday talk show, and Greg Behrendt's Wake Up Call, an ABC prime-timer that targets a couple in crisis and works with them on- and offstage to resolve their problems. On a Saturday break in the middle of a crushing production schedule, Behrendt knows how he looks walking through Barneys—like a man impervious to his age. His latest DVD, Greg Behrendt Is Uncool, is all about guys like him. "I went to see a concert at the Universal Amphitheater," goes one bit. "And the security guard goes, 'Friend Hey, friend! I'm going to have to take that chain wallet from you.' I'm like, 'Because of the war and the terrorism and the upgrade to security?' He's like, 'Nope. Because you're 38.'"

Like any good comedian, Behrendt, who is 43, knows how to arrest an overlooked moment and hold it up to the light for thorough inspection, dangling it at eye level like a mouse by the tail. What catapults his humor to a higher plane is the initial discrepancy between his medium--himself--and his message. Onstage he might strut for a few paces, maybe throw down a rapper gesture for emphasis, but his jokes are spun from a gentle, bemused intellect. They're wry, even professorial, observations about himself from the perspective of the status quo.

Behrendt's persona is that of an introspective tough guy, a wild-man metrosexual who loves his wife, Amiira, to whom he's been married for six years, and is grateful to his parents. He's the anti-Dr. Phil, the white-guy Oprah, a confused or lonely person's guide to cooldom. He's every girl's insight into how men really think. "When I was growing up, there were three things I told my mom I wanted," he says in Mantastic, his break-through 1998 HBO special. "A leisure suit, a princess telephone, and to play football in the NFL." The show, a celebration of feminine-saturated masculinity ("This is magnificent," he says of a gleaming four-slot toaster), ends with a perfect example of the Behrendt synthesis. He leaves the stage and returns to the deafening tones of Motorhead. He's wearing a nondescript woman's housecoat with a Peter Pan collar, open to reveal red plaid boxers, a T-shirt, and ankle boots. He's playing air guitar like a rocker possessed, snapping his head with every chord, marching across the stage, and punishing his invisible instrument.

"This is my favorite place," Behrendt says, walking through Barneys' cosmetics department. "My father and I used to hang out at makeup counters when I was a kid. My friends were like, 'Dude, what are you doing?' I'm like, 'They're filled with girls, man. They smell good, there's lots of them, and they're every age.'" His enthusiasm for women, equal parts lust, respect, and wonderment, is a predisposition that has served him well. In 2001, Michael Patrick King, who produced Mantastic, hired him as a consultant on Sex and the City, the HBO series he executive produced. "Greg is ruthlessly funny and honest," King says. "He does jock stuff and rock stuff, and underneath it all is his incredible openness to the feminine side. I brought in a lot of stars--Julia Sweeney, Merrill Markoe--but Greg was the only guy I thought about bringing in. He's fun, he's totally loving, he's surprising, and he has an edge." Behrendt sat in on story meetings, the straight-guy sounding board for an all-woman team of writers. "We loved how much he loved his wife," says Liz Tuccillo, a story editor and co-writer of He's Just Not That into You. "We couldn't get over it. We're all pretty sarcastic women, and we would have sensed if it was overblown and braggy But he was so low-key. We knew it was true."

One day, during the free-flowing discussions that generated Sex and the City's episodes, a writer talked about a date that seemed to go well, until the man declined an invitation to go back to her place. Why, the writers wondered, would a man do that? They teased, parsed, and shredded their theorems: He had to get up early the next morning; he was intimidated by her; he probably liked her so much he didn't want to move too fast. Behrendt listened. "I think he's just not that into you," he said.

"The minute he said those words, we jumped on him like a pack of wolves," says Tuccillo. "'What about the guy who really is intimidated or whose mother's sick or really does have to get up early or, or ...' Greg had answers for every one of them." The he's-just-not-that-into-you line led to an episode called "Pick-a-Little, Talk-a-Little," but Tuccillo was convinced it had more potential. "There's a book in this," she said to Behrendt. "Nah," he said, but he mentioned it to Amiira. "Liz is right," she said. "Definitely a book."

Tuccillo and Behrendt hunkered down in his garage and wrote He's Just Not That into You: The No-Excuses Truth to Understanding Guys. In chapters like "He's Just Not That into You if He's Not Asking You Out" and "He's Just Not That into You if He Only Wants to See You When He's Drunk," they posited different relationship scenarios followed by how to interpret them and what to do next. The book captures the realities of contemporary dating with laugh-out-loud writing, but it also dispenses smart advice. Behrendt speaks "guy," translating the masculine behaviors women find baffling. His token phrases, like "Don't waste the pretty," trickled into the lexicon. What helped send the book, which has sold more than 2 million copies in 30 countries, to the top of the New York Times best-seller list was that the command to face reality was wrapped in Behrendt's unflagging optimism. "Liz was the realist," says the book's editor, Patrick Price. "Greg was the cheerleader." You're a sexy fox, Behrendt tells the reader over and over. Okay, so this guy doesn't like you. Get out there, hot stuff, and find the man you deserve. Against any but Hollywood odds, Behrendt became a relationship guru for the 21st century.

Cruising the sales racks at Barneys, he is less successful. "Can't wear stripes," he says, eyeing a T-shirt covered with them. "I'm boxy. My hips are as wide as my shoulders." His voice rises a few notches as he adds, "That's okay. The way God intended it." His right eyebrow, a reddish color unrelated to his hair, peaks like a pup tent when he's making a point, and his voice has the paving of someone who knows from last call at a dead-beat bar. He's easy to be around, maybe because there's no visible dissonance between who he is and how he wants to appear. Hair product notwithstanding, he's minus affectation. It doesn't take long to start talking as if you're old high school friends catching up. "What I'm looking for," he says, "is some really good-fitting pants that look like they were bought in a thrift store, old man's pants. The problem with real old man's pants is the waists are too high and the pants are too full. Too much leg for me." We go upstairs for lunch, and he orders a chicken-cranberry salad. "I just have a thing for being able to answer relationship questions," he says when asked how he comes by his newfound career. "I just happen to have a set of values that makes it so I can add up people's equations in my head and not necessarily solve them, but offer what I think a solution could be."

On the Culver City set of The Greg Behrendt Show, a man-size G is inlaid in the wood floor. It s here that Behrendt has a new pulpit, advising guests on ways to jump-start or let go of their relationships--romantic, professional, familial. "Change lives or go home" is his slogan. Behrendt explains the conceit: "We'll take a topic like 'Fix My Husband.' But then we'll get three compelling stories. One is about a guy who needs to get his shit together. He's in love with his Camaro: Camaro boy. He needs to stop. I identify with him as a man. I have a Dodge Magnum--red with sparkles, a Hemi, 18-inch wheels--and it's all I ever want to talk about. However, it really runs third place to my wife and children. So I help him dial that in." His other show,Greg Behrendt's Wake Up Call, has him working with a couple over the course of a week, together and individually, to help them untwist the kinks in their relationship. Originally intended as a midseason replacement, ABC has talked about running it this fall. "Greg's fucking hilarious," says Brian Keith Etheridge, a producer on both shows. "But he'll drop a tear on you."

Behrendt's appreciative that neither set of TV executives has asked him to rein in his look. "I was very unapologetic about who I am," he says. "It's not like I'm punk rock, but I have a definite style, and I don't want to curtail it. For all of the press photos, they didn't care if my tattoos showed or that I was wearing children's jewelry. They asked, 'You know, could you not wear a skull T-shirt?' I said, 'I get it.'" An alternate observation would be that the suits have hired Behrendt because of, not in spite of, his look. "If Dr. Phil's your dad," he says on a promo reel, "and Oprah's the queen and Ellen's your sister, then I'm your big brother."

Behrendt is quick to point out that he is not a doctor or a therapist. "I definitely have opinions, but I'm not passing myself off as an expert," he says. "When I need an expert, I'm going to grab one. My focus is, How do we get from point A to point B every day? Either me telling you, 'Don't date that dumb-ass,' or me and a therapist saying, 'You've got some family shit that needs working out. Don't show up to Thanksgiving this year because you guys are a mess.' I have no ego about this. I'm one voice at the cocktail party. I have opinions, and you can agree with them or not, and you don't hurt my feelings if you don't like them. I 'm not in your head."

Behrendt grew up in Marin County. His father was the station manager at the local NBC affiliate, KRON, and won an Emmy for news direction. He went on to run a video production company with his wife. "My parents were married for 42 years," Greg says. "Their relationship was always the primary one, as opposed to my mom always being about the kids. I think that's a really smart way to run a family."

Greg and his sister, Kristen, who is three years younger, are close. "She's my hero," he says. "When I wrote He's Just Not That into You, I tapped into resources that probably come from years and years of her bad relationships and wanting more for her. 'He didn't call you. He doesn't like you--he should--so move on.' She can make me laugh until I cry." Kristen recently broke up with one of the men in question, thanks in part to Greg's support. "We were a typical brother and sister," she says. "I had crushes on all his friends. He took me to a Van Halen concert for my eighth-grade graduation. He was always the person I went to talk to. He was always my ally. And he was always right."

Behrendt was not a model student. "I had a lot of learning disabilities, so I was funny a lot of the time," he says. "I had a sort of dyslexia-but-not type of thing--bottom line, I couldn't learn shit." His mother, who died three years ago, recognized his comic streak. He dedicated his first book, He's Just Not That into You, to her. "When I was little, she was always 'You're so funny' But I'd say, 'But I'm an athlete!' Then when I got out of college, 'I'm in a band!' My parents thought I was talented. I was like, 'Nah, I'm cool, I'm not talented.'"

He played hooker on the 1981 W.S. National High School Championship rugby team and received a scholarship to the University of Oregon. After he broke his hand, he enrolled in drama. Through it all he was passionate about rock and roll. "He always wanted to be a performer," says Kristen. "When he was in bands, he was more interested in what outfits they wore than in what music they were going to play. He'd look at Aerosmith and think, 'These guys have scarves and eye makeup, and they're getting every girl in the place.'"

After college Behrendt moved to San Francisco. He started a band called Pimp Slap, which became Trouble Gum, which became Bliz. He joined an improv group that included Margaret Cho, who encouraged him to do stand-up. In 1994, he moved to L.A. and started another band, the New Sheridans. He also became part of a gaggle of emerging comics: Ben Stiller, David Cross, Jack Black, Bob Odenkirk, Laura Milligan, and Janeane Garofalo, who became his girlfriend. "He's probably one of the best boyfriends and best friends I ever had," she says. "He looks like he would be kind of a jerk because he's trapped in a big cement block of a frat guy and then he's incredibly nice. You can tell a guy by how they treat their mother and their sister. Greg was unbelievably respectful and kind to the women in his family."

Joe Sehee was part of the crowd, too, with a lounge act called Joey Cheezhee and the Velveeta Underground. "Greg was crafting his stand-up and also very dedicated to his rock and roll," says Sehee. "He was always uninhibited and real and not afraid to be self-deprecating. He would show a lot of vulnerability."

It wasn't easy getting work. "Nobody would put us up at the Improv," Behrendt wrote in the foreword to The Scene, a book of photos from the "comedy underground" by Jenine de Shazer. "We went places where people liked us or didn't seem to mind us--or were just plain empty: bookstores, coffee shops, Laundromats, abandoned restaurants and haunted storefronts." The Un-Cabaret, Beth Lapides's comedy club based at Luna Park on Robertson, was where Industry types gathered, but Behrendt's group was more likely to be found at Tantrum, a fake poetry club created by Milligan, one of his room mates. It was held weekly at the Diamond Room, a basement setup on Hollywood Boulevard where Will Ferrell practiced a goof on Cirque du Soleil and Jack Black and Kyle Gass developed their band, Tenacious D. Behrendt and his friends were a tight crowd who showed up for each others' shows, laughed loudest at each others' jokes, and were known to take over dive bars like the Bailey, across from the old Ambassador Hotel, on any given night. "We'd make a few phone calls, and 70 people would show up," Sehee says. "Shoes would come flying off. We'd Frisbee drink trays down the bar. Greg always struck me as someone who was in control."

His career, though, was nowhere. "I was concerned," says Garofalo. "I did not think Greg was going to find his voice. I've never been wronger. One of our low points was when he asked me point-blank, 'Do you think I'm funny?' and I said, 'No.' We were boyfriend and girlfriend at the time, and we used to drink heavily, so you can imagine how awful that was--a mixture of alcohol and me saying I didn't think he had it." When Garofalo split with Behrendt, "it was a bad breakup," she says. 'Absolutely 100 percent my fault."

He documents some of his more humiliating stabs at reconciliation in It's Called a Break Up Because It's Broken, which he and Amiira wrote as a follow-up to He's Just Not That into You. Among the low points was a late-night phone call to the Paramount Hotel in New York, where Garofalo was living. He was in a state of such inebriation that the desk clerk talked him out of being put through. "I ran with a pretty hard-partying pack," Behrendt says, "but I always pushed it beyond. I always drank more and had drugs. I was bad." He was living with David Cross, the comedian whose cult TV favorite, Mr. Show, was on the air. "I started thinking, 'Let's see, I'm getting up at noon, and my roommate has his own television show,'" Behrendt says. "'Why can't I get anything done? Because I'm hammered all the time. It's not working.'"

On August 12, 1996, he walked into an Alcoholics Anonymous meeting. He has been sober since. "He'd tried a few times before," says Kristen, who'd gotten sober eight years earlier. "I never said anything. He didn't call me until he was two months in."

Behrendt took baby steps to get himself and his career on solid ground. Realizing he was never going to be a rock star, he concentrated on stand-up. He got a catering job at El Cholo. "I loved it," he says. "I liked getting in a van and driving to people's fancy homes. I worked with comics and actors, and we helped each other out." One night he was assigned to a party hosted by United Talent Agency--which repped Garofalo and Cross and other friends. "A guy on the crew said, 'You can stay in the kitchen if it's weird for you,'" Behrendt says. "I go, 'You know what? I'm a waiter. What am I hiding from? Today I'm a guy who caters and does stand-up in coffee shops and occasionally on the road.' I went out and passed hors d'oeuvres."

Today Behrendt is repped by UTA, has two daughters (Bella True, who is four, and Mighty Luna, who is one), and owns a new house with a pool in Studio City. He and Amiira--who wants to start a kids' rock band with the girls--are co-writing another book with the working title It's Just a Fucking Date. The screenplay for He's Just Not That into You, which he wrote with Tuccillo, is parked at New Line. He has reconciled fatherhood with heavy metal in a band he formed called Black Rattle, which does an amp-blowing version of "Itsy-Bitsy Spider." By the end of the year he hopes to restage a show he used to do at Largo, Bring the Rock. "I get actors and writers and musicians to come on and do stand-up about music," he says. 'And then we have a house band that plays whatever music's being talked about."

Behrendt's wedding ring is a thick silver band affixed with a gold crown--signifying that 'Amiira is the king of my heart," he says. A tattoo on his right deltoid has the word AMIIRA in script flanked by two fat little birds. He first met his wife at a party. She didn't remember him when they saw each other again at a music festival in Seattle. "That time, though, I think I saw her checking me out as I walked away," says Behrendt. Maybe, but still she didn't remember him the third time they met, at a hair salon on Fairfax. "We were both getting highlights," Behrendt says, "and we started talking. It's a conversation that's never stopped."

"Greg's so much more centered and grounded since he's been with Amiira," says Kristen. "He's capable of seeing his direction more clearly. He was vulnerable when they met. He said, 'These are my problems,' and she said, 'Okay, here's what you do.' She's so smart." Amiira, who used to sign bands for Epic Records, is a consultant on his reality show and a producer on the talk show. "She's the opposite of Yoko Ono," says producer Etheridge. "You'd think it would be weird to work with someone's wife, but it's so not. She's a great writer, and she has an instinct about people."

'Amiira and I have a lot of room in our relationship to be ourselves and have our own dreams and fantasies," Behrendt says. "We're solid. We don't have any of the little jealousies, and we see the value and the beauty in a person. Once we had dinner with Gwen Stefani and Gavin [Rossdale]. Afterwards, Amiira joked, 'Now that's a couple we could swing with.' I said, 'Amiira, I have a feeling it would be the three of you--I wouldn't be invited. I don't really want to take my shirt off in front of Gwen.'"

The relationship guru is not happy about the way he proposed to his wife. They were in Hawaii with Amiira's parents. After asking them for her hand, he went into the bedroom to pop the question. "I said, 'Oh, wouldn't it be great if we got together and hung out for the rest of our lives,' or some bullshit like that," he says. "I didn't have a ring--it was fumbled. I don't even like talking about it. I didn't do a thing. I didn't do it the way I would now." Amiira agrees it was goofy. "I didn't know I was being proposed to," she says. "He kept saying, 'What are you doing?' I said, 'I'm reading.' 'Oh. So what are you doing?' 'I think I'm still reading, but maybe I'm vacuuming--I'm not sure.' 'We're best friends, right? Like, we should totally be best friends forever.' I said, 'Are you asking me to marry you?'" Six years later it makes little difference. When Amiira left her husband at Barneys earlier in the day to run errands, she took his chin in her hand and kissed him on the lips. "I adore you," she said.