In her latest engaging novel, prolific Irish author Binchy returns to the notion of sea change, addressed in her early work Light a Penny Candle (1983), which chronicled the story of an English girl during WWII who goes to live in Ireland. Here, two women who are strangers to each other--one American, one Irish--trade houses for a summer, each to assuage a terrible loss. Ria, happily married to handsome, prosperous (if slick) real estate developer Danny Lynch, lives in a beautiful old home on Dublin's Tara Road, an enviable address. For nearly 20 years, such world as matters to Ria Lynch congregates in her kitchen: her mother and sister, her two children, many friends, kids' chums and Danny's associates, a whole bright web of connection. When Danny, out of the blue, announces he's leaving home to live with his young pregnant mistress, Ria's life explodes, and the fallout touches everyone. In coping with this shattering blow, Ria agrees to an offered house trade with an American woman who once had real estate dealings with her husband. Ria will live two months in suburban Connecticut, while American Marilyn Vine will come to Ireland to absorb (or evade) her own sorrow--her son's recent death. Once installed on Tara Road, however, the uptight, remote Marilyn is drawn into Ria's neighborhood dramas; Ria brightens Marilyn's American life as well. While the novel asks questions about marriage (how can basically decent people shred their families, hopes and assumptions, and somehow reconstitute their lives?), the real roots of the story lie in female friendship as a source of strength. The pleasures Binchy offers readers are her lively depiction of social connections, feuds and friendships; secrets, lies, alliances, in short, the thicket of Irish everyday life. The American scenes and characters pale by contrast. As usual, all the characters are basically decent people struggling through the morass of daily existence. While the beginning is slow and the end overtidy, once into the heat of the story, readers will find it a charmer. Major ad/promo; BOMC selection; author tour; 20-city TV satellite tour; simultaneous BDD Audio release. (Mar.) FYI: Tara Road is #1 on the London Times bestseller list.