On 10 Nov 1964, DV announced that producer Ross Hunter decided to continue his successful, longtime collaboration with Universal Pictures by signing an exclusive seven-year contract, enabling him to begin development of an original musical comedy titled Thoroughly Modern Millie. A 28 Jan 1965 DV item claimed Hunter hoped to reteam Mary Poppins (1964, see entry) co-stars Julie Andrews and Dick Van Dyke in the leading roles. Although Van Dyke does not appear, a 31 Jan 1966 LAT article confirmed Andrews’s casting, which was made possible due to the delayed production of Star! (1968, see entry). A few months later, the 5 Apr 1966 LAT noted that Carol Channing, James Fox, and Mary Tyler Moore had signed on to round out the principal cast, marking Moore’s first film for Universal since negotiating a seven-year contract with the studio in 1965. Several contemporary sources, including the 9 Feb 1966 LAT, indicated that Channing had left the touring company of Hello, Dolly! in Chicago, IL, to accept the role of "Muzzy Van Hossmere," which was to be her second credited screen appearance. The 24 May 1966 DV stated that actor Jack Soo also bowed out of a stage performance of Flower Drum Song at the Honolulu Concert Hall in Hawaii.
       In a 26 Jun 1966 interview with the LAT, Mary Tyler Moore revealed that the cast spent five weeks rehearsing. Principal photography began 18 May 1966, as reported by a DV production chart two days later. According to the 21 Jul 1966 Los Angeles Sentinel, Jack Soo and Pat Morita, who were of Japanese origin, spent three hours in make-up each day to portray two Chinese henchmen. Items in the 18 Aug 1966 and 1 Dec 1966 editions indicated that actors Wun Lee Mah and Richard Chang also appeared in the picture, with Chang receiving the help of dialect expert George Wray to perfect his Chinese accent.
       The 5 Jan 1967 Los Angeles Sentinel alleged the participation of stuntman Howard Tree, while a 3 Aug 1966 Var brief claimed Angela Dee had a featured role in the film.
       According to the 17 Aug 1966 DV, the Universal studios unit in Universal City, CA, began working Saturdays to accommodate the schedules of Andrews and Moore, as Andrews risked running into overtime salary, and Moore was booked to appear in a musical stage adaptation of Breakfast at Tiffany’s on Broadway. Production wrapped the following month, as indicated by the “New York Sound Track” column of the 28 Sep 1966 Var, which claimed that final scenes had been completed the previous week on location in New York City’s financial district. A 2 Apr 197 NYT article included a quote from Ross Hunter revealing the production cost approximately $5.5 million.
       While the story was original, many featured songs were re-recorded versions of popular 1920s hits. An 18 Jan 1967 Var article reported that Universal was forced to pay licensing fees for most of the songs owned by other studios, including Warner Bros., Metro-Goldwyn-Mayer, and MCA. The 25 May 1966 LAT stated that Hunter consulted with several vintage orchestras, bandleader Paul Whiteman, and Universal recording engineers to achieve the uniquely “tinny” sound of the era. On 24 Jan 1967, LAT reported that Decca Records purchased rights to issue the film’s official soundtrack prior to the film’s release. The album performed extremely well, as the 19 Apr 1967 Var announced it had reached gold record status for $1,000,000 in sales after just four weeks.
       Thoroughly Modern Millie made its world premiere 21 Mar 1967 at New York City’s Criterion Theatre. According to a NYT item published the following day, proceeds benefitted the Museum of the City of New York. Regular engagements began 22 Mar 1967 as a “reserved seat attraction,” with similar hardticket bookings scheduled to begin on the West Coast on 13 Apr 1967. A 10 Mar 1967 LAT item indicated that all earnings from the evening gala event at the Warner Hollywood Theatre in Los Angeles, CA, would be donated to the Crippled Children’s Guild of the Orthopaedic Hospital. A 21 Apr 1967 LAT article revealed that $55,000 was contributed to the construction of the facility’s new $4 million Diagnostic and Treatment Center. The 5 Jan 1967 LAT pointed out that Thoroughly Modern Millie was only the second Universal picture to be exhibited with a roadshow release pattern. Some venues reportedly featured 70mm engagements.
       After several weeks in release on the East Coast, the 12 Apr 1967 Var announced that additional matinee screenings were being added to the Criterion’s early summer schedule to make the film more accessible for Girl Scouts, schools, and youth groups.
       Around this time, the 2 Apr 1967 NYT reported that Hunter was in discussions with potential screenwriters to develop a sequel titled The Jazz Babies, which would reunite Andrews, Channing, and Moore as vaudevillian performers in 1930s New Orleans, LA. However, he disclosed that several previous commitments prevented him from beginning production until later that year, and the project ultimately did not move ahead.
       Elmer Bernstein received an Academy Award for Music (Original Music Score), and the film was nominated in six additional categories: Actress in a Supporting Role (Carol Channing), Art Direction, Costume Design, Music (Scoring of Music—adaptation or treatment), Music (Song), and Sound. Carol Channing won a Golden Globe Award for her performance. Golden Globe nominations also went to Elmer Bernstein for Best Original Score – Motion Picture and Julie Andrews for Actress in a Leading Role – Musical or Comedy. The film was honored with nominations for Best Original Song – Motion Picture, and Best Motion Picture – Musical or Comedy.
       The picture’s popularity later inspired a legitimate stage version of the same name, which debuted at the Marquis Theatre on Broadway on 18 Apr 2002. The show ran for 903 performances, and received eight Tony Awards including Best Musical, as well as four additional nominations.