With the exception of the last three folders in Box 3, all the correspondence is between Psychiana and its many students. Robinson admits in several of his books that, due to lack of space, many thousands of letters were destroyed, which accounts for the fact that the correspondence in this collection does not begin until 1935. There is only one letter in 1935, one folder for letters dated 1936, two folders for 1937, one for 1938, one for 1939, two for 1940, and one for 1941. Then there is a gap before the letters are resumed in 1947 for which there are nine folders. These years are contained in the first file box. The majority of letters are dated 1948, and these occupy one and one half file boxes. The letters for 1949 and the folders of miscellaneous correspondence complete the third box.

The replies to the earlier letters are signed by Frank Robinson and C.W. Tenney, with Robinson's letters being the more personal; Tenney seems to have used a form letter. In 1940 and 1941 W.W. DeBolt was also signing letters, and from 1947 to 1949 Alfred Robinson answered most of the student's letters.

It was claimed that in its first year the Psychiana teaching was sent to 600,000 people in 67 countries, and that it eventually was sent into 74 countries. Included in this sampling of correspondence are letters from all the 48 states, the territories of Alaska, Hawaii, the Panama Canal Zone, and the Canadian provinces, of Alberta, British Columbia, Manitoba, Nova Scotia, Ontario, Quebec, and Saskatchewan. More distant letters came from Australia, Barbados, British Guyana, Ceylon, China, Costa Rica, Cuba, England, Germany, Holland, Jamaica, New Zealand, Philippine Islands, Puerto Rico, South Africa, and the Gold Coast in West Africa--a total of 18 countries. The students came from all economic levels, from the poor and unemployed to laborers, those owning small business such as grocery stores, those employed in management positions in large corporations, doctors, lawyers and even some ministers subscribed to the lessons. Students ranged in age from a young man who began studying Psychiana at the age of 16 to Alex Anderson, who said in his 1948 letter that he was 102 years old. Many wrote year after year giving progress reports and requesting more lessons or books.

Most of the incoming letters tell of benefits received through the study of Psychiana, improved health, better jobs, more harmonious family life, etc. A few letters inquire about missing lessons or letters received from the accounting department, some correct Robinson's Biblical references. In 1937 there are many letters relating to the postal investigation of Psychiana; Dr. Robinson asked his students to send him copies of the letters they sent to the postal inspector in Seattle, and these letters are included in the collection.

Students often sent Robinson newspaper clippings or articles they felt he might be interested in, including one of Herbert W. Armstrong's "World Tomorrow" radio broadcasts, and the pamphlet "The Cult Called Psychiana Exposed by the Sunday School Times" (1939) [Box 1, folder 1940 A-J]. They also included original art work, poems, articles, and music. Many students sent their photographs and photographs of their families.

Among the more interesting letters is one in 1940 in which the writer claims to have had a foreknowledge of Dr. Robinson and Psychiana as early as 1916. There is also, in 1937, a letter from a women in Tacoma mentioning the recovery of her son after a telegram was sent to Robinson for help. From her letter and Robinson's reply it is evident that this is the telegram he mentions in several of his books as the one he read to the audience in Portland's Shrine Auditorium. (see Strange Autobiography, p. 268; also Lecture I, National Convention, 1937 in Box 5) In another 1937 letter a student mentioned to Dr. Robinson that he was copying his lessons to share with others. Robinson immediately replied telling him to stop copying the lessons or he, Robinson, would sue the student for violation of copyright. In 1948 a student sent short book reviews of Robinson's books, the most common criticism being the lack of proof-reading. Another student, a vegetarian, sent her interpretation of the Biblical story of the fall of man saying man's sin was eating meat. In 1949 Alfred received a letter which concluded "You have certain natural endowments, in other words, native ability, you have passed through experiences which brought acquired ability, and these are your personal capital stock, and if you develop this capital stock along the original lines which you surely must be able to do, you will make a good landing, but if you try do what somebody else has done in the same manner, form and spirit, you will end like Bert Hubbard [i.e., you will fail.]" There is one unintentional touch of humor on the part of the Post Office; an envelope addressed "The Archbishop of Psychiana, Moscow, Idaho" was stamped "Missent to Priest River."