This paper provides a general overview of the forces that contributed to the rise and fall of the "new math" movement. It is noted that the movement developed as a response to certain problems in mathematics education; these problems remain to be solved. Some small-scale successes were achieved, from which we can learn. The answer to "What went wrong?" lies, the author believes, in conflicts between the pioneer curriculum reformers and the other groups interested in improving mathematical education, such as professional mathematicians. The work of the Commission on Mathematics is discussed in some detail, and comments on the School Mathematics Study Group (SMSG) are included. The new math, it is found, became "old-fashioned mathematics" presented from a modern point of view, and limited to the vocabulary of modern mathematics; it did not include any significant amount of useful modern mathematics (e.g., linear programming or statistics). References are made throughout the paper to pages from the author's doctoral dissertation, on which the paper is based. (MNS)