The daughter of Myles Fairchild, Kimberly Fairchild accompanied him to Los Angeles from her hometown of Nantucket, Massachusetts when her mother died. Kimberly met Forrester Creations heir Rick Forrester in high school, falling for him despite his involvement with Amber Moore, whom he'd gotten pregnant. Kimberly was encouraged by the fact that no one in Rick's family wanted him with Amber and worked to capitalize on her friendship with him. At Rick and Amber's wedding rehearsal, the lovesick Kimberly suffered through standing in for Amber, then watched Amber exchange vows with Rick.

Kimberly was thunderstruck when she found out her father's real name was Adam Alexander, and that he had been on the run since before Kimberly was born because he had borrowed money from crooked men, then turned them in to the authorities. Though Kimberly had a tough time adjusting, she learned to love having a sister, Adam's older daughter, Macy Alexander. Meanwhile, after Amber had Rick's baby, Kimberly became convinced Amber was hiding something that could destroy her marriage.

Kimberly tried to move on with Macy's half-brother, C.J. Garrison. Kimberly got a chance to model the show-stopper during a Forrester fashion show, but the back of her dress caught on a hook and ripped off, exposing Kimberly's undergarments to the audience. Kimberly forgave C.J., who worked for rival fashion house Spectra Fashions; he hadn't meant to target Kimberly while trying to sabotage the show. Kimberly came to resent Rick's mother, Brooke Logan, who was coming between Macy and her true love Thorne Forrester, even though Brooke supported Kimberly's interest in Rick.

Kimberly saw the tension between Amber and her visiting cousin, Becky Moore, and determined Becky knew what Amber was hiding. Kimberly confronted Amber, and when a catfight ensued, Kimberly used karate on Amber to defend herself. Kimberly flew all the way to Paris but failed to get answers out of Becky. Coming home, Kimberly locked horns with Amber and her mother, Tawny Moore; when Kimberly figured out that Amber's secret had something to do with her baby, Little Eric, Kimberly found Tawny's gun in her face. After Rick asked Kimberly to stop trying to dig up dirt on Amber, Kimberly dated older photographer Giovanni Lorenzano, which didn't please her father at all. While in Venice for a fashion show with Giovanni, Kimberly kept a close watch on Rick, Amber, and Becky.

After it came out that Amber's baby had died at birth and she had replaced it with Becky's child, Kimberly was thrilled that Rick wanted to be with her. But Kimberly's world was rocked when Rick forgave Amber and went back to her, then when Adam, who was afraid his identity had been compromised, told Kimberly he had to leave town. Kimberly supported Macy when Thorne slipped away from her and worried when the recovering alcoholic appeared to be drinking again. Knowing Macy wanted to meet Thorne at the Forrester cabin in Big Bear to end their marriage, Kimberly drove up to check on them and discovered that Macy and Brooke had been in a car that hit a gas truck. Kimberly tended to Brooke, but before Thorne could get to Macy, Kimberly watched in horror as Macy's car exploded.

Learning that Macy had driven erratically because Brooke had beaten Thorne to the cabin and presented Macy with divorce papers, the grieving Kimberly became unstable and targeted Brooke. Enraged, Kimberly confronted Brooke and pushed her through a plate-glass window, but something sparked in her when Thorne tried to calm her down. Kimberly fixated on Thorne and worked to convince him not to marry Brooke, also trying to turn Rick and his sister, Bridget Forrester, against the upcoming nuptials. During a photo shoot, Kimberly rigged a heavy light to fall on Brooke, but Thorne saved her from it.

Kimberly kissed Thorne and tried to seduce him, but when Thorne got drunk after Brooke broke things off for the sake of her kids, Kimberly told Thorne they had slept together. But even that deception didn't stop Thorne's wedding to Brooke, so Kimberly conceded defeat and holed up in the beach house she had inherited from Macy. Kimberly was stunned when Adam showed up on the door, wanting to take Kimberly on the run with him and promising her a miraculous reunion. Kimberly left Los Angeles and hasn't been seen since; Macy turned up alive in Italy, where it is presumed Kimberly is still living.