Brandt worked as a photographer who specialized in new-born babies and was employed as a part-time scout for the Los Angeles Rams based on a recommendation by Elroy Hirsch. In 1958, he was hired as a full-time scout by the San Francisco 49ers. He served as the Dallas Cowboys' chief talent scout since the club's inception in 1960. He had served as a part-time scout for the Los Angeles Rams under General Manager Tex Schramm in the 1950s. When Schramm took command of the newly formed Dallas franchise in 1960, Brandt was one of the first people he hired. Schramm, Brandt and Coach Tom Landry formed the triumvirate which guided the Cowboys for their first 29 years. He helped pioneer many of the scouting techniques used by NFL clubs today, such as:
Creating a new scouting and evaluation system for prospects, which would later spread throughout the NFL. In the NFL Films' documentary series Finding Giants, Ernie Accorsi mentioned how then-general manager George Young built the New York Giants scouting process based on the Cowboys system.
Using computers for scouting and talent evaluations. To achieve this level of automatization, the Cowboys had to systematically define which were the traits, measurable qualities and skills that could be expressed into numbers and formulas in order for a computer to understand them. Different traits were prioritized for different positions.
Helped to create the NFL Scouting Combine as a centralization of the scouting evaluation process.
He also made a reputation of acquiring high draft choices by making impactful trades, which were used to select players like Randy White, Ed "Too Tall" Jones and Tony Dorsett. Brandt's dismissal from the Cowboys on May 2, 1989 completed a purge that began with Jerry Jones' purchase of the franchise just over nine weeks prior on February 25 and also resulted in Landry's ouster and Schramm's resignation.
Personal life
After a few years out of football, he returned as a print analyst and draft expert. He currently contributes to NFL.com as a senior analyst and is a major contributor in selecting the PlayboyAll-Americanfootball team. Brandt has also been responsible for inviting collegiate players to the NFL Draft every year. He is a regular on SiriusXM NFL Radio as a commentator on "Late Hits", "The Endzone", and the "SiriusXM NFL Tailgate Show". He was inducted into the Texas Sports Hall of Fame on April 9, 2015. He was announced as the 22nd member of the Cowboys' Ring of Honor on November 2, 2018. On February 2, 2019, it was announced at the annual NFL Honors Awards that Brandt was elected to the Pro Football Hall of Fame.