Four years ago, just a few months before his runaway best-seller, The Kite Runner, was published, Khaled Hosseini went home to Afghanistan. It was his first visit back in nearly 20 years, and nothing looked the same. Two decades of war had ravaged his country. Every road, every piece of infrastructure was in decay. And then he noticed the women. "It was like they had been made two-dimensional," says Hosseini, 42, of the women he saw walking about in burkas and chadors. "As if there was nothing underneath it." Sitting at a corner table on the 35th-floor restaurant of the Mandarin Oriental Hotel in Manhattan, dressed in a dark pin-striped suit and white shirt, Hosseini looks across Central Park, as if retrieving his thoughts from far away. "That's part of the reason I wanted to write this book," he continues. "You look at a woman walking down the street, and there's a history beneath that burka. There's heartache and hope and there's joy and there's happiness and there's silliness and bitterness, love, envy. All these human things are there under that garment." In A Thousand Splendid Suns, Hosseini writes his way into this enclosed space, bringing to life two very different Afghani women. Mariam is the product of a wealthy businessman's sexual dalliance, who grows up enthralled with the idea of her father. When her mother commits suicide, she is married off at age 14 to a shoe merchant named Rasheed. Their marriage quickly goes downhill as Mariam fails to conceive, while the political situation worsens. Enter Laila. Orphaned in the post-Soviet clashes between moderates and Islamic fundamentalists, her only options become prostitution or marriage. She, too, winds up betrothed to Rasheed, who over the years has become only angrier, more violent, more soured by what's happened to his country. The Kite Runner sold more than 8 million copies around the world and will debut as a feature film this fall. Expectations for this follow-up are high, but so far it seems to have passed the test. The Washington Post's Jonathan Yardley wrote, "Just in case you're curious, just in case you're wondering whether in yours truly's judgment it's as good as The Kite Runner, here's the answer: No. It's better." The week after the review ran the book landed at No. 1 on The New York Times best-seller list. On the morning we talk, such reviews have just begun to break and Hosseini has a look of relief, but the effort of finishing the book still hangs about him. After just one day of promotion, his eyes are tired and squinting. "It was a lot harder" this time around, he says. "There were some days when I thought I had bitten off more than I could chew. And yet you want to prove to yourself you didn't pour out of you everything that you had to say in that first book." Hosseini wrote The Kite Runner in a one-year burst between 5 a.m. and 8 a.m. before he went to work as a physician. He went on a permanent sabbatical from that job two years ago to write, so he had more time to refine his prose, his storytelling, to get this book right, he says. He also had help. When he was in Kabul, Hosseini talked to some of the women, "but with some it was not easy," he laments. There is a large immigrant community of Afghanis in the Bay Area, where he lives, who also helped Hosseini recreate the world of Herat, the town where his parents grew up. Writing his way back into time, he found it hard to avoid one line of thinking. "I kept appreciating, if it weren't for some hand of fate, this could have been my mother," he says, referring to the fact that his family left in 1976. By the time they were ready to return, the communist revolution had begun. His mother, a Farsi and history teacher, never had to live through the control and privations of modern-day Afghanistan. They immigrated to the US in 1980 and lived for a time off welfare. The other woman in Hosseini's life is his wife, Roya, a lawyer, whom he describes as his first and toughest reader. "My wife is honest to a T," he says with a big smile. "If something is not working, she'll let me know right way. Sometimes she can even get angry: 'What are you doing here? What is this?'" At four and six, Hosseini's two children are just beginning to be old enough to realize their father is a big deal. They are also beginning to pull away from him. "They are aware of where their parents are from," Hosseini says with a small wince. "They both speak Farsi... although in the last year or two, as they've been going to school, they have become increasingly reluctant to reply in Farsi, to put it politely." It is clear this piece of friction is troublesome to Hosseini. But it is even clearer, from A Thousand Splendid Suns, that he appreciates their lives could have been lived under the shadow of far graver concerns. The writer is president of the National Book Critics Circle.