Marta Karolyi

In 1981, the Károlyis, along with fellow Hungarian-Romanian team choreographer Géza Pozsár, defected during a gymnastics tour in the United States. They were granted asylum and settled in Oklahoma. The couple's daughter, Andrea, joined them later.

In 1996, Márta was chosen as the head coach of the U.S. women's team for the 1996 Olympics.

After the 1996 Olympics, the Károlyis retired from coaching. However, three years later, Béla returned to the public eye when he was named the national team coordinator for the U.S. women's gymnastics team. His approach was protested and resisted by both the national-team gymnasts and their coaches, who, by the 2000 Olympics, were so frustrated and unhappy that they spoke about the situation publicly.

In 2001, on the recommendation of the U.S. national team coaches, the position was handed over to Márta. While she maintained some aspects of Béla's original program, her approach has been different, and generally more acceptable to the gymnasts and their coaches. It has also yielded impressive competitive results: Between 2001 and 2008, American women won a combined total of 44 medals in World Championship and Olympic competition.

In November 2008, Emilia Eberle, a Romanian national team member during the Károlyi coaching era, gave an interview to KCRA-TV in Sacramento, California, claiming that while she was on the team, both Béla and Márta regularly beat her and her teammates for mistakes they made in practice or competition. "In one word, I can say it was brutal," she told KCRA. Other Romanian team members, including Ecaterina Szabo and Rodica Dunca, as well as Géza Pozsár, the Romanian team choreographer who defected with the Károlyis, have made similar charges of physical abuse. When asked in 2008 to comment on the allegations, Béla Károlyi said: "I ignore it. I'm not even commenting. These people are really trash."

At the 2012 Olympics, after Aly Raisman was given a score of 14.966 in the balance beam final, which put her a tenth of a point behind Cătălina Ponor of Romania, Károlyi requested a video review. As a result of the review, Raisman was awarded an additional tenth of a point for difficulty, allowing her to win the bronze medal on a tie breaker.

She retired from coaching in 2016, after the Olympics at which the US Women Gymnastics Team won nine medals (four gold, four silver, one bronze). Her last group of gymnasts called themselves the Final Five because that was Márta's last Olympics. Valeri Liukin was named as her replacement on 16 September 2016. The Károlyis sold the training facilities at the Karolyi Ranch to USA Gymnastics; however, they continue to own the surrounding land as well as their nearby residence.

On October 28, 2016, a sex abuse lawsuit was filed by a former member gymnast against USA Gymnastics including the Károlyis, alleging they turned a blind eye to molestations by the team doctor Larry Nassar. The former gymnast claims Dr. Nassar repeatedly sexually abused her when she was on the national team from 2006 to 2011.

In January 2018, USA Gymnastics terminated its lease of the Károlyi owned gymnastics training center Karolyi Ranch during the sentencing phase of the trial of Dr. Larry Nassar, who was found guilty of numerous acts of sexual assault against young gymnasts, many of which took place at the facility, where parents were not allowed to be present. A lawsuit was filed against the Károlyis in 2016 alleging that they had known about and "turned a blind-eye to the sexual abuse".

On January 25, 2018, the Ranch announced the permanent closure of the facility on its website. On January 30, 2018, the Texas Ranger Division took over the criminal investigation of the ranch.