Brooks, who is directing and producing, wrote the screenplay, which involves a love triangle. Rudd would play a white-collar executive vying for Witherspoon's affections, while Wilson would portray a professional baseball pitcher who is also a love interest.
As is customary with Brooks' projects, logline is being kept vague for the film, which has the working title "How Do You Know?"
Paula Weinstein ("Blood Diamond") and Laurence Mark ("Dreamgirls") are also producing.
Studio is eyeing an early summer start date.
The only potential snag for Rudd, who has been in high demand since toplining the surprise fall box office hit "Role Models," is that he is also in talks to star in DreamWorks' comedy "Dinner for Schmucks." That film is tentatively scheduled to lense in September. Rudd, who recently teamed with Witherspoon as the voice stars of the upcoming toon feature "Monsters vs. Aliens," next stars in the DreamWorks comedy "I Love You, Man."
Wilson, who most recently appeared in the Christmas hit "Marley and Me," next appears in a supporting role in the sequel "Night at the Museum: Battle of the Smithsonian."