The Strong Interest Inventory® (SII) is the most widely used and respected instrument for career exploration in the world. This
newly revised version is more powerful than ever, as its content reflects the way we work today. That is, the many changes in
the workforce, the very nature of the jobs we do and the mirroring of the U.S. population. In particular, the folks at CPP
(Consulting Psychologists Press) are most proud of the huge sampling size as well as the widest possible range of demographic,
racial, ethnic and socio-economic data gathered so as to ensure the highest level of validity and reliability for the SII. Simply put,
the Strong Interest Inventory® “soldiers-on” with its reputation as being the gold standard in career development. Currently, the
Strong is used by over 70% of North American colleges and universities in some capacity.

At its core level, the SII is based on the idea that individuals are more satisfied and productive when they work in jobs or at
tasks that they find interesting and when they work with people whose interests are similar to their own. To say it in another
way, a person’s interests are compared to thousands of individuals who 1) report being happy in their jobs and 2) are successful
in their jobs.

Again, the Strong Interest Inventory does not examine your abilities and skills; it is an inventory of your interests...hence its
name. The SII will ask you to indicate your preference for a wide range of occupations, school subjects, activities and types of
people. It will take about 30-45 minutes to complete. A person’s highly personalized report identifies optimum career choices
based on interests. It also includes additional related occupations with concise job descriptions. For example, the results may
tell you that your interests are similar to those of engineers who are very satisfied with their career choice. The results do not
tell you what you should be or whether you have an aptitude for the mathematics involved in this career, i.e. whether you would
be good at that job. Click below to see a sample of this highly personalized career interest portrait of what you would be
electronically receiving (in the form of a PDF file) - should you decide to make use of our services. On average, these reports
average 19 pages. That's 19 pages about
your personally.

Prior to the introduction of SII, people's interests in jobs were assessed basically, using four techniques. The earliest of these
techniques was "estimation", which simply involved asking an individual to indicate her or his feelings towards an activity.
Because estimates were not always accurate, individuals often were encouraged to "try-out" activities as another method for
assessing their interests. These try-outs could obviously be quite time-consuming and costly. Next came "rating scales" and
"checklists", but still, these efforts made no attempt to systematically identify people's interests.  By "systematically identifying
people's interests", it is meant that there were no attempts to coordinate questions from one questionnaire to another - or to
see how what patterns of responses (if any) each question evoked. In addition, no attempts were made to correlate on a
grander scale (beyond the individuals themselves) any commonalities between responses and people. In short, each person's
answers became an island unto itself...and worse...the interpretation of that person's responses depended subjectively upon the
personality and/or mood of the person doing the interpreting  on that particular day. All-in-all, not good.    

Then in 1927, psychologist Edward K. Strong Jr. (1884-1963) arrived on the scene introducing the first published systematic
inventory to help people exiting the military (men) find suitable jobs. That is, with his "Strong Vocational Interest Blank", he
used statistical methods to summarize responses to pools of items representing various activities and occupations. He came out
with a version for women in 1938. For its time, Strong's inventory was "good", but by today's highly sophisticated research
standards, it was still a rather blunt instrument.

A few years after Strong's death in 1963, Dr. David Campbell, then a professor of psychology at the University of Minnesota,
undertook a major revision of the Inventory and in 1974, introduced the Strong-Campbell Interest Inventory. It wasn't long
before the S-CII became very well known in the vocational world. Without question, however, the greatest boost to the
credibility of the Strong came with the thoroughly researched and subsequent introduction of the third and fourth revisions (1981
and 1985). This all happened with co-author Jo-Ida Hansen, Ph.D. As a highly regarded professor who was also in the
Department of Psychology at the University of Minnesota, Hansen continues to direct the Center for Interest Measurement
Research and the Ph.D. Program in Counseling Psychology at UM.

The most recent revision of the SII (2004), includes all of the best research over the decades of Strong, Campbell and Hansen as
well as the typology of psychologist John L. Holland. The "Holland Codes" were introduced in 1985 and are based on the theory
of vocational choice. At its simplest, this theory proposes that "birds of the same feather flock together." In other words, people
like to be around others who have similar personalities - and (job-wise) people who report being successful in their jobs. Re-
stated, in choosing a career, it means that people choose jobs where they can be both successful and simultaneously be around
other people who are like them in their personalities. The newly revised SII consists of 291 items, each of which asks you to
indicate your preference from five responses (strongly dislike, dislike, indifferent, like, strongly like).  

Meanwhile, David Campbell has chosen to singularly focus on creative leadership and his Campbell Interest and Skill Survey®
(CISS) is doing extremely well. Campbell is the H. Smith Richardson Senior Fellow at the Center for Creative Leadership (CCL),
which is a nonprofit educational institution founded in 1970 and headquartered in Greensboro, N.C. Among other
accomplishments, he has served as a visiting professor at the University of Utah and Duke University as well as been an
honorary research fellow at the University of London and a distinguished visiting professor at the U.S. Air Force Academy.
Strong Interest Inventory:
considered to be the gold standard in career search assessments.
Strong Interest Inventory® - a short history
®