My Uncle, Oscar Hammerstein « Commentary Magazine:
For the next several hours, Oscar went over every line, every lyric, every stage direction. Sondheim said that at the end of this crash course in musical theater by one of its masters, he knew how to write for himself. Oscar continued to mentor, advise, encourage, and caution Sondheim until his death 15 years later. By that time, Sondheim had written the lyrics to West Side Story and Gypsy and was on the cusp of one of the most extraordinary careers in musical-theater history, one that would be as theatrically daring as Oscar’s own, and perhaps as significant.