Grant Chambers was a fashion designer who attended Northwestern University and had a romantic involvement with Taylor Hayes, who had become a psychiatrist. Grant got a job at prestigious design house Forrester Creations and ran into Taylor, who was still hung up on her ex-husband, Ridge Forrester. Grant told Taylor she shouldn't wait for Ridge but didn't wait for Taylor when his neighbor, Sheila Carter, came onto him. Grant wasn't aware of Sheila's criminal past or stint in a psychiatric hospital, though he did get clues when Sheila became obsessive after only a few kisses. Grant then came upon Clarke Garrison, a cad who had treated his sister, Kelly Chambers, badly; Grant wasted no time punching Clarke in the face.

Grant wanted Taylor but got impatient and started casually seeing Michael Lai, not realizing she had a serious thing for him. Grant got one romantic date with Taylor before she decided to move away because of Ridge; Grant rented Taylor's beach house and took Michael on as a roommate. Meanwhile, Grant became pals with Ridge and started working with Ridge's ex-wife/girlfriend, Brooke Logan, on the Forrester men's line. Grant was attracted to Brooke, but when Michael called him on it, Grant gave Michael a kiss. Grant lent Brooke an ear and offered New Age advice when she had problems with Ridge, then took the city girl to a country western bar. Grant and Michael double dated with Ridge and Brooke, but Grant and Brooke kissed when they found themselves alone together.

Grant fell for Brooke, but when she insisted she loved Ridge, Grant took Michael to bed. Grant sulked when the showing of the men's line was postponed; Grant accepted Brooke's reassurances and gave her a friendship kiss. Grant knew Ridge wanted to propose to Brooke on the runway but was as shocked as Brooke when Ridge proposed to Taylor instead! Grant found out Ridge knew about the kiss and tried to explain, getting punched and fired for his efforts. Grant was allowed his men's line showing; at the end, Grant's jaw dropped when Brooke proposed to him in front of Ridge and the fashion press. Grant knew Brooke had done it to get to Ridge but accepted the challenge to win Brooke over. Grant hated hurting Michael, who read him the riot act for leading her on.

Grant enjoyed the promotion and subsequent luxuries that Brooke gave him at Forrester. Grant and Brooke did their best to make Ridge jealous, though Grant held out hope that Brooke would take their engagement seriously. Grant ruffled feathers throwing his weight around Forrester when Brooke put him in charge of the company. Things also didn't go well when Grant told Brooke's kids, the teenaged Rick Forrester and grade-schooler Bridget Forrester, that he was marrying their mother. Grant suggested to Brooke that they set their wedding date ahead of Ridge and Taylor's so it might inspire Ridge to take action; Grant arranged to marry Brooke on a yacht, stung when Brooke stalled, hoping Ridge would stop the ceremony. Grant finally took Brooke as his wife but his heart fell when Brooke wouldn't make love to him.

Grant found out that the captain who performed his wedding to Brooke was a fraud but kept quiet about their invalid marriage. Resentful because of the leash he felt the Forresters were putting on him at the company, and feeling Brooke was constantly being hurt by her association with them, Grant talked majority stockholder Brooke into signing over control of Forrester Creations to him. Grant's power grab gained him a slew of enemies at Forrester; one night while alone in his office, Grant took a bullet to the shoulder. Grant blamed Ridge and sent him to jail, but when an investigator started sniffing around on Ridge's behalf, Grant secretly admitted to Ridge that he had been shot by hostile teen Rick, who hated Grant and had been descending into a world of heavy metal and violent video games. Grant wanted to protect Rick, who had no memory of his crime, and begged Ridge to keep Rick out of juvenile hall, following through on his promise to get Rick help.

News got out that Grant's marriage to Brooke wasn't legal; when she refused to make it so because she still loved Ridge, Grant quit Forrester and angrily took his designs to ailing competitor Spectra Fashions as revenge. Grant got to know Spectra's grand diva owner, Sally Spectra, and her daughter, Macy Alexander; since Macy was still heartbroken over her divorce from Ridge's brother, Thorne Forrester, Grant felt he and Macy had being dismissed by the Forresters in common. Grant's friendship with Macy turned flirtatious, then romantic, but Grant put his foot in his mouth by making a production of asking her to sleep with him when she thought he was going to propose. Grant tried to make up for it by actually popping the question, taking it in stride when Macy adamantly refused him. However, Grant's relationship with Macy progressed, and together they bought the Insomnia Coffee House, where Macy returned to her roots as a singer. Eventually Grant wore down Macy's resistance and married her at the Insomnia with the Spectra gang in attendance.

Grant became suspicious when Sally's friend, Lauren Fenmore, began dating Johnny Carerra, the twin brother of the deceased "Rush" Carerra, who had held Lauren and Ridge's father, Eric Forrester, hostage in Greenland after a plane crash. Grant's instincts were correct: "Rush" had survived, taken Johnny's place, and tried to kill Lauren. Later, Grant was perturbed when he and Macy moved into a house on the beach and their next-door neighbor turned out to be Thorne; Grant sensed Thorne wanted Macy back and told her ex-husband to back off. Grant hired up-and-coming R&B star Raymond Usher to sing at the Insomnia, which helped solidify the coffee house.

Grant and Macy were trying for a baby but it wasn't working; Grant was relieved when Macy saw a doctor and found out she was fine. However, when Grant went for his own check-up, he discovered he was sterile. Grant was still grappling with the frustration of not being able to give Macy a baby when he learned that his lack of sperm count was caused by Stage III testicular cancer, which was spreading to other parts of his body. Grant confided in Macy's best friend, Darla Einstein, but initially wanted to spare Macy the news. By the time Grant told Macy, he had decided Thorne should give her the baby she wanted once he was gone.

Grant adopted a Zen attitude about his diagnosis but ended up in the hospital, where he battled pneumonia and played down how much pain he was in for Macy's benefit. Grant deteriorated within weeks and arranged to have himself taken off the machines, asking Macy to sing for him. By the time Macy had finished her song, Grant had passed away.