In 1936 Arlington installed the first photo-finish camera in Chicago racing. Four years later they installed the first electric starting gate in Chicago racing. In 1967 they installed the largest closed-circuit color TV in all of the sports.
In 1971 the track hosted the first commercially sponsored $100,000 race in the U.S. - the Pontiac Grand Prix. Trifecta wagering was introduced in 1971 and in 1981 Arlington hosted the first ever million dollar race for thoroughbreds - the Arlington Million. Bad news struck in 1985 as a fire devastated the original grandstand facility. In 1987 with a victory at Arlington, Jack Van Berg becomes the first trainer to win 5,000 races. In 1989 Arlington re-opened as Arlington International Racecourse.
In 1996 Arlington hosted the Arlington Citation Challenge, in which Cigar tied Citation's record for 16 consecutive victories. That same year the park hosted a simulcast of the first Dubai World Cup, the world's first $4 million race, in North and South America. In 2000 Arlington reopened after a two-year absence.
In September, Arlington Park and Churchill Downs Incorporated completed their merger and the track name reverted back to Arlington Park.