A professional scientific study of children that remember previous lives was initiated by Dr. Ian Stevenson, professor of psychiatry at the University of Virginia School of Medicine, in the late 1960s. Since then Ian Stevenson has gathered close to 3000 cases of children that remember previous lives, often as named, identifiable persons. Stevenson's cases have been gathered from Ceylon, India, Alaska, Thailand, Brazil, Burma, Turkey, West Africa, Lebanon and the USA. Stevenson has published 65 detailed reports about his findings in which the information the children remembered has been matched with the data of their former identity, family, residence and manner of death. Birthmarks and scars on the children have been found to match the experiences from the remembered previous life, especially in cases of violent deaths.

Typically a case begins when a child around the age of 3 without any kind of prompting begins to speak of a former life. The child will mention people and places that nobody in his family has heard about before and will, in certain cases, describe details of his former death. The child will be quite insistent in claiming to have a different name, and he will tell his astounded parents that he is, in fact, somebody else. He may also say that he has other parents or a wife or children that live in a different city or even a different country. The child continues talking about it for several years, generally to the great annoyance of the parents.

When Stevenson, through a network of helpers, learns about such a child, he arranges a visit and takes notes of all the data that the child recounts. If possible, Stevenson arranges that the child be taken to the town where he says he lived before. At this visit the child will then typically lead the way through the streets to his former home and will spontaneously recognize and greet persons like old friend calling them by their pet names. When the child enters the house, where he lived before, he will comment upon changes in the decoration, will ask about persons and things that he thinks are missing and remember events from the past. In certain cases he reveals knowledge about secret hiding places or where the family gold is hidden, about family debts or old scandals, all of which is confirmed to be true by the surviving family of the former personality. The child knows nothing about the time after the death of his former personality.

From Stevenson's book "Twenty Cases Suggestive of Reincarnation" the case of Swarnlata can be mentioned.
Swarnlata was born in 1949 in Pradesh in India into a middle class family. She started to talk about a former life at the age of three when one day her father was taking her for a ride and they passed the town of Katni, which was more than 100 miles from their home. Swarnlata suddenly pointed out the window and asked the chauffeur to turn down a street to "my house", where she said they could get a better cup of tea than on the highway. She told her father more than 50 facts about her life in Katni and the father made a note of these. She said that her name was Biya Pathak and that she had two sons. She described every detail of her home and how there was a railway behind her house. She said that she had died from a throat disease and was treated by a Dr. S.C. Bhabrat in Jabalpur. In 1959, when Swarnlata was 10 years old, news about the case reached Ian Stevenson and he initiated an investigation. He found the house where the Pathak family lived using only Swarnlata's description and he found everything just as Swarnlata had described it. He interviewed the Pathak family that informed him that Biya Pathak had died in 1939 and had left two sons and a husband. A few months later Biya's husband, her brother and one of her sons traveled to the town where Swarnlata lived in order to see her and test her memories. Swarnlata knew nothing about their arrival and they arrived at her house in the company of nine other persons and hid their identity. Swarnlata immediately recognized her (Biya's) brother and called him by his pet name. Afterwards she recognized her husband and behaved in a subservient manner as befitted a Hindu wife. She also recognized her son who had been 13 years old when she died. She reminded her husband that he had hidden 1200 rupees from Biya before she died and that the money had been in a particular box when he took it, which he confirmed to be true. A few weeks later Swarnlata visited her "former home" in Katni for the first time and she immediately commented on changes in the house and she identified the room where Biya had died. She revealed intimate details from the life of the family, she recognized old servants and commented in a good-humored way on how things had changed during the last 20 years. She had no knowledge of events after 1939.

Swarnlata's story is so well documented that it clearly points to her being the reincarnation of Biya Pathak. Ian Stevenson can with certainly rule out that Swarnlata had any normal way of knowing the intimate details she revealed about Biya. She had never been to Katni in her life as Swarnlata, nor did she have any kind of knowledge about the Pathak family. Yet she knew their most intimate secrets and a large number of details about their life. This strongly suggests reincarnation. However, Ian Stevenson never claims that he has proved that reincarnation is a fact; he merely cautiously says that his cases suggest that reincarnation happens. Stevenson's work is of monumental proportions and nobody who has studied his work can avoid being impressed by the meticulous care and strictly scientific approach with which he has carried out his research.

Ian Stevenson has mainly published monographies for the scientific community, but the following books have been published for the general reader: "Twenty Cases Suggestive of Reincarnation" and "Where Biology and Reincarnation Intersect". In his book "Old Souls" journalist Tom Shroder pays a tribute to Ian Stevenson's work and gives an account of his working methods during field trips to India and Lebanon.

Carol Bowman is an American researcher who herself has gathered several hundred cases of children with past life memories. Her cases are mainly from the USA and have been offered to her by parents who suspected that specific behavioral patterns in their children could have their origin in former lives.

Carol Bowman has published two books about her findings: "Children's Past Lives. How Past Life Memories Affect Your Child" and "Return from Heaven".