His son is former American Federal Communications Commission (FCC) commissioner Nicholas Johnson.
Considered one of the earliest and most influential speech pathologists in the field, he spent most of his life trying to find the cause and cure for stuttering – through teaching, research, scholarly and other writing, lecturing, supervision of graduate students, and persuading K-12 schools, the Veterans Administration and other institutions of the need for speech pathologists. He played a major role in the creation of the American Speech and Hearing Association. In 1930 Johnson published the book Because I Stutter, based on his master's thesis, which describes his struggles with stuttering from an autobiographical perspective.
The stutterer, if I may speak for him as a type, does not want pity any more than he wants contempt, but he does want the understanding which the normal respect of one human being for another makes possible. He is a human being, trying to make a stutterer's adaptation to a world of glib speakers.
Johnson's book People in Quandaries: The Semantics of Personal Adjustment (1946; still in print from the Institute of General Semantics) is an excellent introduction to general semantics applied to psychotherapy. In 1956 his Your Most Enchanted Listener was published; in 1972, his Living With Change: The Semantics of Coping, a collection of selected portions of transcriptions of hundreds of his talks, organized by Dorothy Moeller, provided further general semantic insights. He also published many articles in his lifetime, in journals, including ETC: A Review of General Semantics.  Neil Postman acknowledges the influence of People in Quandaries in his own excellent general semantics book Crazy Talk, Stupid Talk (1976, Delacorte, New York):
I am tempted to say that there are two kinds of people in the world – those who will learn something from this book (People in Quandaries
) and those who will not. The best blessing I can give you is to wish that as you go through life you will be surrounded by the former and neglected by the latter.
Patricia Zebrowski, University of Iowa assistant professor of speech pathology and audiology, notes, "The body of data that resulted from Johnson's work on children who stutter and their parents is still the largest collection of scientific information on the subject of stuttering onset. Although new work has determined that children who stutter are doing something different in their speech production than non-stutterers, Johnson was the first to talk about the importance of a stutterer's thoughts, attitudes, beliefs, and feelings. We still don't know what causes stuttering, but the 'Iowa' way of approaching study and treatment is still heavily influenced by Johnson, but with an added emphasis on speech production."
One of the most thorough single Web site collections of material regarding Wendell Johnson is http://www.uiowa.edu/~cyberlaw/oldinav/wjhome.html. It contains links to his Who's Who in America entry and c.v., bibliographies, excerpts from his writing, audio of his general semantics lectures, articles by others about Johnson, and an excerpt from Robert Goldfarb, editor, Ethics: A Case Study from Fluency (2005).
Attacks on the 1930s master's thesis, and the journalistic labeling as a "Monster Study", contributed to controversy. On the one hand, speech research scientists Nicoline Grinager Ambrose and Ehud Yairi are critical of the conclusions that Mary Tudor drew from her data, but believe that no harm was done to the subjects and that there was no intention to do harm. Others felt the study was unethical by today's standards but fell within the bounds of those standards in 1939.
On the other hand, Richard Schwartz concludes in Chapter 6 of the book that the study "was unfortunate in Tudor and Johnson's lack of regard for the potential harm to the children who participated and in their selection of institutionalized children simply because they were easily available. The deception and the apparent lack of debriefing were also not justifiable." Other authors concur claiming the orphan experiment was not within the ethical boundaries of acceptable research. The University of Iowa paid a settlement to some of the surviving subjects of over $900,000 in 2007.