The Bedlam Series is the name given to the Oklahoma–Oklahoma State rivalry. It refers to the athletics rivalry between Oklahoma State University Cowboys and Cowgirls and the University of Oklahoma Sooners of the Big 12 Conference. Both schools were also members of the Big Eight Conference before the formation of the Big 12 Conference in 1996, and both were divisional rivals in the Big 12 South Division prior to 2011. The rivalry will conclude as an annual conference matchup in 2023, after which Oklahoma will officially join the Southeastern Conference. 40 years of the rivalry's games were played without the teams playing in the same conference, and it is possible that the series may continue beyond that date.