When Dmitry Medvedev dined with the Obamas in July, the Russian president appeared both relaxed and powerful. He hit that elusive note by pairing his fine blazer, crisp buttoned shirt, and expensive-looking leather-soled shoes with dark, straight jeans.

Power jeans are increasingly common in high-ranking business and political circles. Indeed, jeans are now a legitimate part of the global power-dress lexicon, worn to influential confabs where the wearers want to signal they're serious -- but not fussy -- and innovative.

The look started with the young but has crossed into gray-haired circles. In preparation for a meeting with the U.S. president of Swiss watchmaker IWC, Larry Seiden, a 56-year-old fine-watch collector from San Jose, Calif., bought a pair of black Agave jeans from a high-end boutique. 'They tailored them for me and I have to tell you, I really love them,' he says. 'Now I'm thinking of getting another pair in blue denim.'

Jeans are recruiting new fans among even dressy executives. 'I'm not really a jeans guy,' said Gilles Mendel, chief executive and designer of J. Mendel furs and evening wear, not long ago, sitting in his New York office. Still, he went with a snug set of dark blue Acme jeans under a black Dior blazer.

Chosen well, jeans can suggest the wearer is confident and modern. Traditionally cut blue jeans carry a whiff of the laborer about them, so denim on a leader suggests a willingness to roll up the sleeves and dig in. There's also something of the rebel in a pair of jeans. In the boardroom, that can read as creative.

But jeans must be carefully paired with a pressed shirt and good shoes to be elevated to business class. And some industries haven't (yet) become open to denim as power wear. Banks and accounting-firm boardrooms, for instance, remain decidedlywoolen. New York-based careeradviser Jonscott Turco says jeans are generally a 'no-brainer' in the media, manufacturing and creative industries, but not in financial services and law firms.

Power jeans may best be left to the executives in mixed-rank groups. Being a junior person wearing jeans in a room full of pinstripes could spell 'youthful blunder.' Perhaps the best rule is that of the high-priced boutique: If you have to ask, you can't afford to wear them.

It's also possible to go awry with the wrong jeans in the right place. Barack Obama, whose wife and children have been heralded as fashion icons, was ridiculed for wearing dorky 'dad jeans' (baggy and high-rise) to pitch at an All-Star game. When Tony Blair wore jeans to meet George Bush two years ago, the British prime minister was criticized for his pants' snug fit.

Few items of clothing speak as loudly, to the positive or negative, as a pair of jeans. As with tuxedos and Hawaiian shirts, wear them right (on the latter, only to a luau if you're a mainlander), or not at all.

To wit, fit is as essential for jeans as for tailored slacks. Eric Jennings, Saks Fifth Avenue men's fashion director, suggests that men keep their executive jeans 'dark and straight.' And never dress as if the jeans had been switched out from formal suit pants at the last minute: No fancy French-cuffed shirts with jeans, he advises.

In fact, getting power jeans right involves lots of no's. No distressed jeans at work. No metal studs. No acid washes. No lavishembroidery. No boot cut. No skinny. No pedal pushers, shorts or cutoffs. No baggy high-rise. No super-low-rise. No holes. And no fussy ironing.

From their 19th-century origins until the 1950s, jeans were mainly work wear. Levi's historian Lynn Downey says denim was demonized in the '50s with wearers like James Dean and Marlon Brando. Nothing could have been better for sales. 'Denim was code for rebellion,' she says. 'So every young boy wanted to wear it.'

We have Steve Jobs to thank for today's power jeans. His uniform of Levi's 501s and a black turtleneck was synonymous with innovation in the '90s; now, in the tech world, dressy pants can be viewed with suspicion. 'When someone shows up to an interview or meeting in anything other than jeans, it shows inexperience and a lack of confidence,' says Andrew Dumont, vice president of marketing for text-messaging company Tatango.

Little wonder that the folks at Levi's are reverential toward Apple's founder. Steve Jobs, says You Nguyen, a Levi's executive in charge of women's merchandising and design, 'is the Marlon Brando of his time.'

Christina Binkley

• preparation [,prepə´reiʃən] n.准备；预习(时间) (初中英语单词)
• executive [ig´zekjutiv] a.行政的 n.行政官 (初中英语单词)
• instance [´instəns] n.例子，实例，例证 (初中英语单词)
• career [kə´riə] n.经历；生涯；职业 (初中英语单词)
• financial [fi´nænʃəl] a.金融的，财政的 (初中英语单词)
• junior [´dʒu:niə] a.年少的 n.年少者 (初中英语单词)
• minister [´ministə] n.部长；大臣 v.伺候 (初中英语单词)
• essential [i´senʃəl] a.必需的 n.要素，要点 (初中英语单词)
• director [di´rektə] n.指导者；....长；导演 (初中英语单词)
• formal [´fɔ:məl] a.正式的；外表的 (初中英语单词)
• mainly [´meinli] ad.主要地；大体上 (初中英语单词)
• suspicion [sə´spiʃən] n.怀(猜)疑；嫌疑 (初中英语单词)
• interview [´intəvju:] n.&vt.接见；会见；交谈 (初中英语单词)
• charge [tʃɑ:dʒ] v.收费；冲锋 n.费用 (初中英语单词)
• legitimate [li´dʒitimit] a.合法的 vt.使合法 (高中英语单词)
• influential [,influ´enʃəl] a.有力的，有影响的 (高中英语单词)
• confident [´kɔnfidənt] a.有信心的，自信的 (高中英语单词)
• laborer [´leibərə] (=labourer) n.工人 (高中英语单词)
• decidedly [di´saididli] ad.坚决地，果断地 (高中英语单词)
• adviser [əd´vaizə] n.顾问 =advisor (高中英语单词)
• positive [´pɔzətiv] a.确定的 (高中英语单词)
• negative [´negətiv] a.否定的 n.否定词 (高中英语单词)
• historian [his´tɔ:riən] n.历史学家 (高中英语单词)
• founder [´faundə] n.奠基者 v.陷落 (高中英语单词)
• increasingly [in´kri:siŋli] ad.日益，愈加 (英语四级单词)
• collector [kə´lektə] n.收款(税)员；收藏家 (英语四级单词)
• woolen [´wulən] a.毛线的；毛织品的 (英语四级单词)
• creative [kri:´eitiv] a.有创造力的；创作的 (英语四级单词)
• lavish [´læviʃ] a.慷慨的；浪费的 (英语四级单词)
• embroidery [im´brɔidəri] n.刺绣(品) (英语四级单词)
• designer [di´zainə] n.设计者 (英语六级单词)
• willingness [´wiliŋnis] n.情愿，乐意，自愿 (英语六级单词)
• innovation [,inə´veiʃən] n.改革；革新；创新 (英语六级单词)