Here is a sampling of what they had to say:
Eric Grode in his Broadway.com Review: "The Light in the Piazza is incredibly lucky to have found Victoria Clark. Her shrewd, poignant portrayal, imbuing Margaret's hesitant emotional growth and deep-rooted pragmatism with a lush singing voice, is by far the highlight of Guettel and Lucas' affecting, occasionally overreaching adaptation of the Elizabeth Spencer novel. Luckily, Clark gets enough help from her talented supporting cast, Bartlett Sher's crystalline direction and an exquisite physical production to vault Piazza over its dramaturgical gaps."
Ben Brantley of The New York Times: "Played by Victoria Clark in what is hands down the best musical performance by an actress this season, Mrs. Johnson infuses the tired old woes and wonders of midlife disenchantment and autumnal romance with freshening shadow and light. Otherwise, the show, which has been given a sumptuous production under the direction of Bartlett Sher, is notable for looking and sounding pretty and confused… Mr. Guettel's evocations of pure and radiant young love, which involve a lot of breathlessly protracted 'ah's' by Fabrizio and Clara, are simply lovely. They also become very irritating. The songs of anxiety and dissonance are more persuasive."
Howard Kissel of The New York Daily News: "Adam Guettel's score for The Light in the Piazza is the best piece of theater music since Stephen Sondheim's Passion, lo, 11 years ago. Guettel has captured the delicate, sometimes painful, ultimately radiant moods of Elizabeth Spencer's story… Spencer's novel… presents difficulties Craig Lucas' book has not solved. At times, for example, he depicts the Italian characters as caricatures. At other times, their responses are unexpectedly grim. Elsewhere, his writing is clever to the point of becoming annoying. It is a great tribute to Guettel's score that he surmounts all these obstacles. This is also a tribute to the extraordinary cast."
David Rooney of Variety: "Exquisite as Bartlett Sher's production of The Light in the Piazza is on so many levels, it's ultimately the single element of a mother's emotional journey that resonates, due in large part to the flawlessly calibrated work of Victoria Clark, lending poignancy, grace and truth to a problematic show… While it takes considerable time to identify the slender story's chief themes, Lucas' book is descriptive and sensitively observed, by far the more successful half of the collaboration. It's the music that seems ill-conceived and unsatisfying."
Michael Kuchwara of The Associated Press: "This enchanting musical celebrates the unexpectedness and intensity of it all, no matter what the roadblocks, and does it with style. Piazza is a show of considerable beauty--more melodically, emotionally and visually satisfying than any other musical this season."