She was born-again at the age of 14 in the Methodist Church of Concordia, and began preaching in the West at the age of sixteen in primarily Baptist Churches. Kuhlman traveled extensively around the United States and in many other countries holding "healing crusades" between the 1940s and 1970s. She had a weekly TV program in the 1960s and 1970s called I Believe In Miracles that was aired nationally. The foundation was established in 1954, and its Canadian branch in 1970. Joan Gieson became her assistant for 8½ years.
Following a 1967 fellowship in Philadelphia, Dr. William A. Nolen conducted a case study of 23 people who claimed to have been cured during her services. Nolen's long term follow-ups concluded there were no cures in those cases;another medical doctor, H. Richard Casdorph, refuted Nolen's charges. Furthermore, one woman who was said to have been cured of spinal cancer took off her brace and ran across the stage at Kuhlman's command; her spine collapsed the following day and she died four months later.Roberts Lairdon tells us: "...a five year old boy, crippled from birth, walked to Kathryn's platform without assistance. Another, a woman, who had been crippled and confined to a wheelchair for twelve years, walked to the platform without the aid of her husband. A man...who had received a pacemaker eight months earlier, felt intense pain in his chest after Kathryn laid hands on him. Returning home, he found the scar gone from his chest where the pacemaker had been implanted. Later, when the doctor took X-rays, he discovered the pacemaker was gone and the man's heart healed! It was common for tumors to dissolve, cancers fall off, the blind see and the deaf to hear. Migraine headaches were healed instantly...it would be impossible to list all the miracles that the ministry of Kathryn Kuhlman witnessed! God alone knows."
By 1970 she moved to Los Angeles conducting faith healing for thousands of people each day as an heir to Aimee Semple McPherson. She became well-known despite, as she told reporters, having no theological training. She married Burroughs A. Waltrip of Dallas, in which city he left his wife and two children, to marry Kuhlman in Iowa City, Iowa. She described Waltrip as "the best-looking guy there ever was". They soon divorced, as Kuhlman explained, "because he was divorced I had to choose between him and my work".
In 1975, Kuhlman was sued by Paul Bartholomew, her personal administrator, who claimed she kept $1 million in jewelry and $1 million in fine art hidden away and sued her for $430,500 for breach of contract. Two former associates accused her in the lawsuit of diverting funds and illegally removing records, which she denied and