Jessica Marcelli was YPSO's founding Music Director and Conductor. Introductory remarks by Wallace H. Miller at YPSO's first concert, December 4, 1937:

Ladies and Gentlemen: It is a pleasure to welcome such a large and enthusiastic audience to the First Concert of the Young People's Symphony Orchestra. 
I believe a brief history of this organization would be of interest to you. A little over a year ago a small group of young people started a neighborhood orchestra in Berkeley, meeting in the home of Mrs. Orlin J. Bell, our secretary. It grew in size and scope until our present conductor offered her services to the young people. New quarters were obtained for rehearsals and several music lovers became interested in the group.

About two moths ago a permanent organization was effected, a constitution was adopted and tonight's concert was arranged. I will read from our Constitution the objects of the Association, as follows: to stimulate musical interest; to develop talent among the young people of the EAST BAY cities; to provide them with an added opportunity for orchestra training and the reading of standard orchestral scores under skilled leadership; to co-operate with the public schools, private teachers and all other organizations and individuals, in the interest of fine music and the maintaining of the highest musical standards; and to give public performances as often as the conductor and the Board of Directors deem desirable.

Conductor and Cofounder of YPSO, Jessica Marcelli was a former member of the San Diego Symphony. She was trained in the music centers of both America and Europe under such teachers as George W. Chadwick, Joseph Adamowski, Felix Winternitz, Henry Sverdrofsky, Carl Flesch and Karl Muck, conductor of the Boston Symphony. In her unbounded vision, faith, and understanding, Mrs. Marcelli had a rare gift as a leader of young musicians. Her fine musical ability brought national recognition to YPSO in a very short time. Mrs. Marcelli led YPSO for over twenty-two years, endearing herself to young and old alike, and inspired the highest ideals in musicianship, fairness, discipline, loyalty, and affection.

Adapted from YPSO 60th anniversary brochure.