Jhumpa Lahiri’s stories are extraordinarily place-specific and character-faithful. Most of her fiction is set in and around Boston, Massachusetts, or is in some way connected to the city, and concerns a small, narrow demographic: educated middle class Bengalis making their way in what was once called the new world. Her interest is the minutiae of Bengali family life as it is lived outside India; how families are affected by geographic separation, cultural slippage and merging, and miscegenation. She herself is of Bengali Indian descent and lives in New York.

In three interconnected stories in Unaccustomed Earth – ‘Once in a Lifetime’, ‘Year’s End’, ‘Going Ashore’ – Lahiri follows the fortunes of two Massachusetts-based Bengali families. She shows how the various members interact with one another across the years as they seek to remake themselves in a new country while they attempt, with difficulty, to remain faithful to a larger cultural inheritance.

In ‘Year’s End’ Kaushik, a student, returns home to spend Christmas with his father who has recently married again to a woman with two young daughters. Kaushik is still mourning his dead mother, and he is angry and hurt that his father has remarried, not least because the marriage was “arranged by relatives” in India. His stepmother, from Calcutta, speaks very little English; having lived in America for so long, Kaushik speaks little Bengali. They address each other with mutual incomprehension.

This is the set up for what becomes a closely observed study of cultural misunderstanding within one family – the stepmother is as welcoming and open as Kaushik is guarded and truculent. As always in Lahiri’s stories of domestic realism, there’s an epiphany towards the end, in this instance a moment of sudden self-revelation as Kaushik discovers within himself a capacity for violence that changes fundamentally the way he perceives his father and his new wife.

Though inevitable, Lahiri’s epiphanies never feel forced or unearned. In ‘Unaccustomed Earth’, the title story, a daughter – who, like Kaushik, is also mourning a dead mother – discovers a letter written by her aged father who has been living with her. This alters her understanding of the father whom she considered to be a closed-in man, incapable of the love she had always sought from him but never received.

Lahiri isn’t a noisy or ostentatious writer; it’s impossible to think of her writing a story about an Islamic terrorist or the assassination of a politician, let alone the events of September 11 2001. She’s not interested in fiction-as-documentary, in bringing urgent news of the times in which we live. If she has a fault, it’s that her sentences can be too detailed, too overstuffed with superfluous information about her characters’ lives: their thoughts, hopes, yearnings and aspirations.

She mostly writes in delicately poised sentences of unusual precision and clarity, but there can be occasional inelegancies too, usually resulting from her desire to make her sentences too full, as in this example from ‘Unaccustomed Earth’: “She decided that it must have been the food she found herself always finishing off Akash’s plate and the fact that now she had to drive everywhere instead of walk.”

Lahiri is presently probably the most influential writer of fiction in America. Her quiet, richly textured stores are read, studied and widely imitated by the unceasing flow of graduates emerging as if on a conveyor belt from the American universities’ MFA programmes – I know, because most of them send their stories to me. (If a quarter of those wanting to be published in Granta actually subscribed to the magazine, it would be a runaway bestseller!)

My favourite of all Lahiri’s stories is ‘Sexy’, from her first collection, the Pulitzer Prize-winning Interpreter of Maladies (2000). Miranda is a naïve young American living in Boston who, after a chance meeting, finds herself, in spite of herself, falling in love with a complacently married Bengali investment banker named Dev. His life is a labyrinth of lies and betrayals. But he is charming and attentive enough, and Miranda is excited as much by his cultural difference – the Bengali he speaks, his religion, the stories he tells her of Indian family life – as she is by the man himself. The story is richly comic, and yet poignant, because this is a relationship that will never have the chance to mature or deepen. So graceful and nuanced are Lahiri’s observations, and so dense are her paragraphs in incidental but telling detail, that it’s miraculous to observe how much Miranda changes over the course of one short story. By the end she is an entirely different woman: alone, much wiser, but sadder too. Most miraculous of all is how the story quickens in the final paragraphs as it suddenly enlarges, flaring out from the particularity of Miranda’s loss to the generality of Boston on a cold winter afternoon. We see Miranda sitting outside a church, and as she drinks coffee, her head beginning to clear of all the confusion, she becomes aware of the giant pillars and dome of the church and the transcendent “clear-blue sky spread over the city”.

This new collection also ends with a story of disappointed love, ‘Going Ashore’. Kaushik, now in early middle age, is a hard-travelling photo-journalist, with a flat in Rome. It is there in the city that, by chance one evening, he meets Hema, a fellow Bengali-American whom he knew many years before in Boston. They are both confused and adrift but for a few brief weeks they lose themselves in a rapture of mutuality and fellow feeling. But Hema is soon to return to Massachusetts to be married. She knows that if she leaves Kaushik behind she will never know happiness again – but leave him behind is what she does, with disastrous consequences. ‘Going Ashore’ is perhaps the saddest story Lahiri has ever written, and yet you finish it feeling only uplifted by the artistry and sheer mastery of technique.