1946 – Founded by Howard F. Webb of the Houston Independent School District and Coralie Gregory Wood, former music supervisor for the Houston Parks and Recreation Department. The first concert was held December 28, 1946 in the City Auditorium. The organization consisted of three orchestras, Advanced (65 musicians), Intermediate (25 musicians) and Beginner (15 musicians).

1948 - Houston Youth Symphony undertakes a performance tour of Mexico, including a concert in Mexico City.

1955 – The organization expands its mission to include ballet training in addition to the symphony orchestra and is reincorporated as the 501(c)3 nonprofit The Houston Youth Symphony and Ballet.

1978 – Paul H. Kirby appointed Music Director

1984 – First international concert tour, performing in three Canadian cities.

1997 – Dr. Michael Webster appointed Artistic Director and conductor of the HYS Symphony.

1998 – HYS performs at the inaugural ceremonies for Houston Mayor Lee P. Brown.

1998 – HYS’s Philharmonia orchestra performs a Holiday Concert at Jones Hall with the Houston Children’s Chorus and Houston Masterworks Chorus.

1999 – HYS performs in the Texas/Georgia Music Festival at Carnegie Hall.

2001 – The ballet component is spun-off into Allegro Ballet and the organization returns to its original focus on music and operates under the legally assumed name of Houston Youth Symphony.

2002 – HYS Symphony orchestra performs at the National Youth Orchestra Festival in Sarasota, Florida.

2004 – HYS expands with the establishment of a fourth orchestra, the Sinfonia.

2005 – HYS Symphony orchestra performs in a side-by-side concert with the Houston Symphony for its Salute to Educators concert. (This becomes a recurring partnership every 3 years.)

2005 – HYS Melody Program (formerly known as HYS Star Program) is established to bring private music instruction to talented children from economically disadvantaged backgrounds.

2008 – HYS receives the first of five “Mark of Excellence Awards” from the Foundaiton for Music Education.

2009 – HYS launches its Chamber Music Program.

2010 – HYS receives the first of two “American Prize” awards for outstanding youth orchestra.

2011 – HYS Chamber Music partners with the St. Cecilia Chamber Music Society.

2012 - The HYS Symphony is invited to perform on the nationally syndicated NPR program "From the Top." Hosted by pianist Christopher O'Reilly, the concert was recorded in the Wortham Center's Brown Theater, and co-presented by Houston's Classical 91.7 Radio. Episode 254 aired nationally on September 9, 2012.

2013 – HYS celebrated its 65th anniversary with a special concert featuring the Symphony in a performance of Beethoven's "Choral Fantasy" with special guests Houston Masterworks Chorus and pianist Timothy Hester.

2015 - HYS launches its Coda Music Program.

2016 - HYS launches its fifth orchestra, the HYS Preparatory Orchestra.