I found it difficult to determine the theory or theories underlying the OICS. The published information was vague: "In developing this tool, Knowdell referenced the concept of 'career clusters' to help develop insight into occupational interests. The OICS workbook also references the work of Richard Bolles and John Holland, who grouped jobs into clusters to help organize thoughts around careers" (Fields, 2013, p. 483). So... meaning what, exactly?
In an APCDA webinar in 2023, Professor Rich Feller talked about the legacy of Dick Knowdell. He spoke about how Dick had made a life's work from helping others, quoting Dick as saying, "We want to take career coaching into organizations". Through writing "his book, Building a Career Development Program, [Dick] tried to do that by working in organizations. He [Dick Knowdell] was attentive to the whole notion of the economy and what it meant. And [it was from] his work in Lawrence Livermore Lab [which...] really allowed him to stay in touch to the workers and the transitions they were going through" (2023, 3:59). I felt that Professor Feller really saw Dick Knowdell as a realistic, grounded person who created tools that would smooth the path of clients into work. At the conclusion of the presentation, Professor Feller invited anyone who wanted to know more to email him.
So I emailed Professor Feller, who kindly explained "Dick picked job titles and coded them according to the RIASEC codes. The theory suggests that if you have these interests they would match others in that job title" (personal communication, 8 October 2025). If we watch the video below, at around a minute in, we can see that each of Dick Knowdell's OICS cards have a three letter RIASEC code on the top left-hand corner (Rich Feller, 2020).
Professor Feller went onto clarify that although "John Holland popularize[d] that [RIASEC] model and commercialized it through his writing and products", we tend to "identify [our] interests based upon their exposure. You can like or dislike thinks according to your exposure to it. In many cases one’s only exposure is through a stereotype. That is why interest can change once a person has more in-depth exposure to it. Interests do not confirm aptitude to have the potential to do the job" (Rich Feller, personal communication, 8 October 2025). A very good point, that.
Dick Knowdell created this card sort as he found the Strongs inventory didn't seem to work so well for women (2003). He wanted something less confining, and "described the card sort process as an activity similar to the card game called Solitaire" where clients deal the "deck of cards [...] by grouping and sorting [into...] categories depending on [their...] assessment [then...] rank[ing] these categories by the [...] level of [...] interest [...] complet[ing] this solitaire process rather quickly by deferring to [...] gut instinct rather doing a deep reflection process" (Campos, 2019, p. 271). Fast and dirty, so the client gets to their 'under mind' (Blyton, 1952, p. 81).
So now we know.
Sam
References:
Blyton, E. (1952). The story of my life. Grafton.
Campos, T. M. (2019). Chapter 37: Knowdell Card Sorts. In K. B. Stoltz, S. R. Barclay (Eds.). A Comprehensive Guide to Career Assessment (7th ed., pp. 269-277). National Career Development Association (NCDA).
Carlson, S., Morningstar, M., Ghosh, A., & Munandar, V. (2020). Exploring the Use of an Occupational Interests Card Sort with Youth with Intellectual Disability: A Preliminary Study. Journal of Inclusive Postsecondary Education, 2(2), 1-20. https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1040&context=sped_fac
Dik, B. J., & Rottinghaus, P. J. (2013). Chapter 19: Assessments of interests. In K. F. Geisinger, B. A. Bracken, J. F. Carlson, J.-I. C. Hansen, N. R. Kuncel, S. P. Reise, & M. C. Rodriguez (Eds.), APA Handbook of Testing and Assessment in Psychology (Vol. 2. Testing and assessment in clinical and counseling psychology, pp. 325–348). American Psychological Association. https://doi.org/10.1037/14048-019
Feller, R. (2023). Dick Knowdell and the Career Development Network's (CDN) Future [Sunday May 22] [video]. Asia Pacific Career Development Conference. https://asiapacificcda.vids.io/videos/449fdbb7191ae2cccd/503_dick-knowdell-and-the-career-development-networks-cdn-future-by-rich-feller
Rich Feller. (2020, November 18). Knowdell Occupational Interest Cards [video]. YouTube. https://youtu.be/rYdLw0o57vA
Fields, J. R. (2013). Knowdell card sorts: Career Values Card Sort, Motivated Skills Card Sort, and Occupational Interests Card Sort. In C. Wood & D. G. Hays (Eds.), A Counselor's Guide to Career Assessment Instruments (6th ed., pp. 481-486). National Career Development Association (NCDA).
Knowdell, R. L. (2003). Card sort career assessment tools. Career Planning and Adult Development Journal, 19(2), 150-159. https://www.stemcareer.com/richfeller/pages/journals/Career%20Planning%20and%20Adult%20Development%20Summer%202003/pdf/Chapter%2014.pdf
Training Systems Inc. (2026). Occupational Interests Card Sort (Knowdell) [image]. https://www.clsr.ca/wp-content/uploads/2020/12/600vd_1.jpg














