Keirsey Temperament Sorter-II (KTS®-II)

1. Abstract

The Keirsey Temperament Sorter-II (KTS®-II) is a 70-item, forced-choice self-report personality inventory designed to evaluate psychological temperament and behavioral tendencies. Developed by clinical psychologist David West Keirsey as an operationalization and significant theoretical departure from both Carl Gustav Jung‘s cognitive type theory and the Myers-Briggs Type Indicator (MBTI), the KTS®-II focuses on observable behavior, communication styles, and action patterns rather than unobservable internal cognitive mechanics. The instrument classifies individuals into four broad, overarching temperaments: Guardians (SJ), Artisans (SP), Idealists (NF), and Rationals (NT), which are further divided into sixteen distinct character role variants mapped across four bipolar preferences: Extraversion–Introversion (E/I), Sensing–Intuition (S/N), Thinking–Feeling (T/F), and Judging–Perceiving (J/P). An additional demographic item assesses respondent gender, yielding 71 items in standard electronic and self-scoring administrations.

The response format utilizes a dichotomous, forced-choice structure requiring respondents to select between two paired alternative behavioral statements. Psychometrically, the KTS®-II demonstrates moderate-to-strong internal consistency across its four dimensional scales, with reported Cronbach’s alpha coefficients typically ranging from 0.70 to 0.86, and test-retest reliability coefficients ranging between 0.74 and 0.89 across multi-week testing intervals. Factor analytic evaluations reveal a predominantly four-factor structure corresponding to the primary preference dimensions, although methodological debates persist regarding the psychometric properties of ipsative forced-choice scoring formats. The KTS®-II has gained extensive global utilization in executive coaching, organizational development, higher education counseling, military leadership profiling, and marital psychotherapy, serving as an accessible, behavior-oriented assessment of human character and interpersonal dynamics.

2. Keywords

Keirsey Temperament Sorter-II, KTS-II, David Keirsey, temperament theory, personality assessment, Artisans, Guardians, Idealists, Rationals, psychometrics, MBTI, behavioral typology, forced-choice inventory, character analysis, occupational profiling.

3. Authors

The primary architect of the temperament model and the instrument is David West Keirsey, Ph.D. (1921–2013). Dr. Keirsey was an American clinical psychologist, professor emeritus at California State University, Fullerton, and a veteran educational psychologist with over three decades of clinical practice working with children, families, and academic institutions.

The original iteration of the instrument, the Keirsey Temperament Sorter, was co-authored with Marilyn M. Bates, Ph.D., and formally introduced in their seminal 1978 text, Please Understand Me: Character and Temperament Types. Dr. Keirsey subsequently refined the theoretical foundation, subscale alignment, and psychometric structure of the inventory, culminating in the publication of the Keirsey Temperament Sorter-II (KTS®-II) in his 1998 monograph, Please Understand Me II: Temperament, Character, Intelligence. Ongoing psychometric research, corporate assessments, and commercial licensing are managed through Keirsey.com and Prometheus Nemesis Book Company.

4. Purpose

The overarching purpose of the Keirsey Temperament Sorter-II is to systematically assess and categorize stable, observable configurations of human behavior, communication habits, and social orientation. While historically linked to Jungian personality type discourse, Keirsey formulated the KTS®-II to serve as a pragmatic, behaviorally grounded instrument capable of identifying an individual’s operational temperament without requiring inference into unconscious, intrapsychic constructs.

The clinical, educational, and organizational purposes of the KTS®-II encompass:

• Self-Awareness and Personal Development: Assisting individuals in identifying their intrinsic core motivations, environmental preferences, interpersonal stressors, and default interaction styles.
• Organizational Consulting and Team Building: Enabling corporate leaders, human resource professionals, and team facilitators to map the behavioral diversity of workgroups, resolve chronic interpersonal friction, optimize role assignment according to temperament strengths, and foster synergy between complementary character types.
• Career Exploration and Vocational Placement: Guiding high school students, university undergraduates, and career transitioners toward professional pathways that align naturally with their communication habits (concrete versus abstract) and action orientations (utilitarian versus cooperative).
• Marital and Relational Psychotherapy: Clarifying systemic communication mismatches between partners. Keirsey posited that marital conflict often stems from the misattribution of malicious intent to benign differences in temperament; understanding one’s partner as an Artisan, Guardian, Idealist, or Rational provides a non-pathologizing framework for conflict resolution.
• Pedagogy and Educational Design: Aiding educators in developing differentiated instructional strategies that cater to the diverse learning modalities of concrete learners (Guardians and Artisans) and abstract learners (Idealists and Rationals).

From an applied perspective, the KTS®-II provides a bridge between complex clinical typology and functional everyday observation. Rather than diagnosing psychopathology, the sorter catalogs natural variations in normal human temperament, operating on the premise that human diversity is neither arbitrary nor pathological, but patterned and predictable.

5. Psychological Construct

The psychological construct underlying the KTS®-II is temperament, operationalized as an individual’s characteristic, observable configuration of attitudes, linguistic patterns, instrumental actions, and psychological needs. Keirsey distinguished his construct from Jung’s cognitive function theory by arguing that internal cognitive processes (such as introverted intuition or extraverted thinking) are inherently untestable and speculative. Instead, Keirsey organized temperament along two fundamental, intersecting behavioral axes: Words (Communication) and Deeds (Action).

The Two Fundamental Behavioral Axes

• Communication: Concrete vs. Abstract:
  • Concrete Communicators (Sensors – S): Individuals who ground their language in reality, immediate facts, practical utility, details, and tangible phenomena. They talk primarily about what is observable, real, and verifiable.
  • Abstract Communicators (Intuitives – N): Individuals who frame their speech around ideas, principles, conceptual models, analogies, dreams, and theoretical possibilities. They focus on what can be imagined or deduced.
• Action: Utilitarian (Pragmatic) vs. Cooperative:
  • Utilitarian/Pragmatic Actors (Artisans and Rationals): Individuals who prioritize functional efficacy and outcomes. They use whatever means are effective to accomplish a goal, regarding standard operating procedures or social norms as secondary to empirical success.
  • Cooperative Actors (Guardians and Idealists): Individuals who prioritize procedural integrity, social harmony, ethical alignment, and normative consensus. They insist on doing things the right way, valuing adherence to established customs, institutional rules, or moral mandates over sheer expedience.

The Four Core Temperaments

Crossing these two orthogonal dimensions produces the four primary temperaments that form the theoretical core of the KTS®-II:

• Guardians (SJ — Concrete Cooperative): Primarily motivated by security, duty, social responsibility, and institutional maintenance. Guardians take pride in dependability, respect authority, value tradition, and maintain societal stability. They include four role variants: Supervisors (ESTJ), Inspectors (ISTJ), Providers (ESFJ), and Protectors (ISFJ).
• Artisans (SP — Concrete Utilitarian): Primarily motivated by freedom of action, tactile impact, spontaneous execution, and tactical problem-solving. Artisans value agility, immediate sensory experience, virtuosity, and adaptable performance. They encompass four role variants: Promoters (ESTP), Crafters (ISTP), Performers (ESFP), and Composers (ISFP).
• Idealists (NF — Abstract Cooperative): Primarily motivated by personal meaning, authenticity, self-actualization, and human potential. Idealists seek profound connections, emphasize empathy, pursue ethical alignment, and champion interpersonal growth. Their four role variants include: Teachers (ENFJ), Counselors (INFJ), Champions (ENFP), and Healers (INFP).
• Rationals (NT — Abstract Utilitarian): Primarily motivated by competence, mastery, systemic logic, and theoretical coherence. Rationals analyze complex mechanisms, ruthlessly eliminate inefficiency, pursue scientific precision, and seek strategic mastery. Their four role variants are: Fieldmarshals (ENTJ), Masterminds (INTJ), Inventors (ENTP), and Architects (INTP).

The Four Bipolar Preference Dimensions

In addition to the primary four-temperament matrix, the KTS®-II evaluates individual scores across the traditional four structural preferences derived from Jungian typology:

1. Extraversion (E) vs. Introversion (I): Sociability, energy direction, and expressive range. Extraverts draw energy from social contact, group engagement, and rapid external verbalization; Introverts conserve energy through solitude, selective interaction, and reflective contemplation.
2. Sensing (S) vs. Intuition (N): Information gathering and linguistic focus. Sensors prioritize empirical observation, practical facts, and present realities; Intuitives prioritize holistic patterns, conceptual synthesis, and future implications.
3. Thinking (T) vs. Feeling (F): Evaluation and decision-making criteria. Thinkers rely on detached, objective logic, consistent principles, and critical analysis; Feelers prioritize personal values, relational harmony, social ethics, and subjective impact.
4. Judging (J) vs. Perceiving (P): Lifestyle orientation and project execution. Judgers seek closure, scheduling, early decisions, and structured environments; Perceivers seek flexibility, open options, spontaneous adaptation, and tentative planning.

6. Theoretical Framework

The theoretical framework of the Keirsey Temperament Sorter-II represents a synthesis of classical humorism, twentieth-century European characterology, and American behavioral typology. Keirsey explicitly traced the genealogy of temperament back over two millennia, asserting that human personality structure has been repeatedly observed and categorized into four recurring patterns across distinct civilizations.

Historical Precedents of Fourfold Typologies

Keirsey positioned his four temperaments as direct modern correlates of historical typology systems documented in the medical and philosophical literature:

• Hippocrates and Galen: The four classical humors—Melancholic (SJ / Guardian), Sanguine (SP / Artisan), Choleric (NT / Rational), and Phlegmatic (NF / Idealist, though Keirsey realigned the mapping to highlight functional behavioral congruence).
• Paracelsus (16th Century): Four elemental spirits representing basic character styles: Gnomes (laborious guardians of earth), Salamanders (passionate actors of fire), Sylphs (curious observers of air), and Undines (empathic creatures of water).
• Ernst Kretschmer and Eduard Spranger (Early 20th Century): Character categories based on morphological predispositions and foundational value orientations (e.g., Spranger’s economic, political, theoretical, social, religious, and aesthetic types).

Divergence from Carl Jung and Isabel Briggs Myers

While the KTS®-II adopts the 16-letter nomenclature developed by Isabel Briggs Myers and Katharine Cook Briggs, Keirsey’s conceptual foundation diverges fundamentally from Jungian analytical psychology:

1. Observable Action vs. Unconscious Mechanism: Jung’s 1921 work, Psychological Types, hypothesized internal, mentalistic constructs—specifically introverted and extraverted attitudes applied to four mental functions (Thinking, Feeling, Sensation, Intuition). Keirsey rejected this cognitive model as unobservable and unscientific, adopting instead an ethological and behavioral perspective grounded in linguistics, social customs, and observable habits.
2. Rejection of Function Hierarchies: Keirsey explicitly dismissed the concept of dominant, auxiliary, tertiary, and inferior cognitive functions. In Myers’ model, an INTP is primarily an introverted thinking type whose auxiliary function is extraverted intuition. Keirsey argued that grouping types by cognitive stacks obscures the higher-order behavioral similarities between all Rationals (NTs) or all Guardians (SJs). Keirsey maintained that an INTP shares fundamental temperament DNA with an ENTJ, ENTP, and INTJ because all four are abstract, utilitarian communicators seeking knowledge and competence.
3. The Primacy of Temperament Over Isolated Dimensions: Rather than viewing personality as the mechanical addition of four independent traits ($E + N + F + P$), Keirsey maintained that the whole temperament (e.g., Idealist / NF) is an integrated, organic gestalt that fundamentally shapes how extraversion or introversion is expressed.

7. Validity

The psychometric validity of the Keirsey Temperament Sorter-II has been investigated across multiple academic disciplines, including organizational psychology, counseling, nursing education, and psychometric evaluation.

Construct and Structural Validity

Construct validity evaluates whether the test items effectively operationalize the intended psychological dimensions. Studies examining the structural validity of the KTS-II have confirmed that items load predominantly onto four distinct latent constructs corresponding to the E/I, S/N, T/F, and J/P dimensions. Research utilizing confirmatory factor analysis (CFA) for categorical and dichotomous variables has shown acceptable model fit indices (e.g., Comparative Fit Index $[CFI] > 0.90$, Root Mean Square Error of Approximation $[RMSEA] < 0.06$) when items are specified to load on their designated dichotomous axes. However, psychometricians have noted that several items—particularly within the T/F and S/N domains—display moderate cross-loadings, reflecting the natural semantic overlap between intellectual curiosity (Rationality) and imaginative vision (Idealism).

Convergent and Concurrent Validity

The convergent validity of the KTS and KTS-II has been assessed primarily through direct comparison with the Myers-Briggs Type Indicator (MBTI® Form G and Form M):

• Cross-Instrument Concordance: Correlation analyses between corresponding raw continuous scales of the KTS-II and MBTI show high concordance rates, typically ranging between $r = 0.74$ and $r = 0.89$. The strongest convergence is routinely found along the Extraversion–Introversion ($r \approx 0.84 – 0.89$) and Judging–Perceiving ($r \approx 0.78 – 0.85$) dimensions.
• Four-Letter Type Agreement: Studies assessing exact four-letter categorical type matches between the KTS-II and the MBTI report full 4-factor type agreement rates between 50% and 65%, with 3-out-of-4 preference matches exceeding 85% to 90%. These rates align with the expected concordance between two independent forced-choice inventories measuring similar psychological constructs.
• Big Five Convergent Patterns: Correlational studies linking the KTS-II preference dimensions to the Five-Factor Model (FFM / Big Five personality traits) demonstrate expected and theoretically robust associations: Extraversion (E/I) strongly correlates with NEO-PI Extraversion ($r > 0.70$); Sensing–Intuition (S/N) correlates strongly with Openness to Experience ($r \approx 0.55 – 0.65$); Thinking–Feeling (T/F) correlates with Agreeableness ($r \approx 0.45 – 0.58$); and Judging–Perceiving (J/P) correlates with Conscientiousness ($r \approx 0.50 – 0.62$).

Criterion and Predictive Validity

Predictive validity studies have documented meaningful relationships between KTS-II temperament classifications and occupational self-selection, leadership behaviors, and educational outcomes:

• Vocational Distribution: Empirical investigations in higher education show significant clustering of temperaments within academic majors: engineering, computer science, and physics faculties show disproportionately high concentrations of Rationals (NT); nursing, primary education, and social work show high concentrations of Idealists (NF) and Guardians (SJ); while culinary arts, performing arts, and emergency services exhibit higher Artisan (SP) representation.
• Management Performance: In organizational settings, Guardians (SJ) and Rationals (NT) consistently demonstrate higher frequencies of managerial promotion in bureaucratic and hierarchical corporations, whereas Artisans (SP) excel in high-volatility, tactical environments such as startups, crisis intervention, and negotiations.

8. Reliability

The reliability of the Keirsey Temperament Sorter-II has been subjected to empirical evaluation utilizing internal consistency metrics, split-half reliability, and test-retest temporal stability coefficients.

Internal Consistency Reliability

Across validation samples in collegiate and adult working populations, the four primary bipolar subscales of the KTS-II exhibit acceptable to strong internal consistency coefficients:

• Extraversion–Introversion (E/I): Cronbach’s alpha values consistently range from $\alpha = 0.78$ to $0.86$. This scale demonstrates the highest internal consistency, driven by unambiguous behavioral queries regarding social interaction, verbalization, and crowd engagement.
• Sensing–Intuition (S/N): Reported alpha values range from $\alpha = 0.72$ to $0.81$. Items querying practical focus versus speculative imagination display robust internal coherence.
• Thinking–Feeling (T/F): Reported alpha values typically range between $\alpha = 0.70$ and $0.79$. While psychometrically acceptable, this dimension occasionally demonstrates minor variation across cultural and gender cohorts, reflecting linguistic nuances surrounding words like “sentiment,” “justice,” and “sympathy.”
• Judging–Perceiving (J/P): Alpha coefficients range from $\alpha = 0.76$ to $0.83$, indicating strong reliability in assessing preferences for closure, punctuality, structure, and spontaneity.

Temporal Stability (Test-Retest Reliability)

Studies evaluating the test-retest reliability of the KTS-II across intervals ranging from two weeks to three months demonstrate stable temporal properties:

• At a two-to-four-week interval, Pearson correlation coefficients ($r$) for continuous dimensional scores range from $0.78$ to $0.88$ across the four scales.
• At extended six-month intervals, stability coefficients remain moderate-to-high, ranging from $r = 0.68$ to $0.79$.
• Categorical stability—the percentage of respondents retaining their exact primary temperament classification (SJ, SP, NF, NT) upon retesting—routinely exceeds 75% to 82%, while full four-letter type replication hovers between 60% and 70%, which is typical for typological self-report instruments.

9. Factor Analysis

The internal dimensionality of the KTS-II has been examined via exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) to verify whether its 70 temperament items appropriately reflect the four-factor structural model proposed by Keirsey.

Exploratory Factor Structure

In early exploratory investigations utilizing principal component analysis (PCA) with varimax rotation on dichotomously scored items, the scree plot and eigenvalue analysis consistently reveal four dominant factors with eigenvalues greater than 1.0, accounting for between 38% and 48% of the total variance:

• Factor 1 (Extraversion vs. Introversion): Items assessing conversational habits, party behavior, phone answering preferences, and privacy load strongly and cleanly on this factor (typical factor loadings: $0.45 – 0.75$).
• Factor 2 (Judging vs. Perceiving): Items measuring punctuality, closure, schedules, work clutter, and procedural deadlines load onto Factor 2 (loadings: $0.40 – 0.71$).
• Factor 3 (Sensing vs. Intuition): Items evaluating concrete observation, literal interpretation, facts, common sense, and theoretical speculation cluster on Factor 3 (loadings: $0.38 – 0.68$).
• Factor 4 (Thinking vs. Feeling): Items contrasting logical analysis, thick skin, justice, firm management, and sympathetic understanding define Factor 4 (loadings: $0.36 – 0.66$).

Confirmatory Factor Analysis (CFA)

When subjected to contemporary CFA techniques designed for binary data (such as Weighted Least Squares with Mean and Variance adjustment – WLSMV), the four-factor orthogonal model exhibits reasonable fit to empirical data:

• Root Mean Square Error of Approximation (RMSEA): Values typically range between $0.042$ and $0.058$, falling well within the conventional threshold for acceptable fit ($< 0.06$).
• Comparative Fit Index (CFI) & Tucker-Lewis Index (TLI): Typical CFI values range between $0.905$ and $0.935$, while TLI values hover between $0.895$ and $0.925$.
• Standardized Root Mean Squared Residual (SRMR): Values generally remain below $0.065$.

While the four-factor model provides the best overall empirical fit, methodological researchers have observed that a hierarchical or bifactor structure—incorporating higher-order constructs representing Concrete vs. Abstract Communication and Utilitarian vs. Cooperative Action—provides valuable explanatory power, supporting Keirsey’s theoretical thesis that the SJ/SP/NF/NT temperaments constitute distinct, integrated behavioral typologies rather than isolated additive traits.

10. Instrument / Measurement Tool

• Test Type: Self-report psychological temperament inventory / behavioral personality typology sorter.
• Format: Available in paper-and-pencil self-scoring matrices, computerized client software, and online web assessments.
• Item Count: 71 total items (70 forced-choice temperament items evaluating psychological preferences, plus 1 concluding demographic item assessing respondent gender).
• Response Format: Forced-choice dichotomous format. Each item presents a prompt followed by two mutually exclusive behavioral alternatives (Option A vs. Option B). Respondents must select the option that most accurately reflects their natural inclinations, preferences, or behavior.
• Scale Structure & Item Distribution:
  • Extraversion (E) vs. Introversion (I): 10 items.
  • Sensing (S) vs. Intuition (N): 20 items.
  • Thinking (T) vs. Feeling (F): 20 items.
  • Judging (J) vs. Perceiving (P): 20 items.
• Scoring and Categorization Rules:
  • Each item is assigned to one of the four dimensional scales (E/I, S/N, T/F, or J/P).
  • Responses corresponding to one pole (e.g., E, S, T, or J) are summed to generate raw subscale point totals, which are contrasted against the alternate pole (I, N, F, or P).
  • The dominant score on each axis designates the individual’s categorical preference letter, producing a four-letter profile code (e.g., ISTJ, ENFP, INTJ, ESTP).
  • The combination of the information-gathering axis (S or N) and the operational axis (J/P for S types; T/F for N types) defines the individual’s core Keirsey Temperament:
    • SJ: Guardian (Supervisors – ESTJ, Inspectors – ISTJ, Providers – ESFJ, Protectors – ISFJ).
    • SP: Artisan (Promoters – ESTP, Crafters – ISTP, Performers – ESFP, Composers – ISFP).
    • NF: Idealist (Teachers – ENFJ, Counselors – INFJ, Champions – ENFP, Healers – INFP).
    • NT: Rational (Fieldmarshals – ENTJ, Masterminds – INTJ, Inventors – ENTP, Architects – INTP).

11. Permissions & Fee and Test Year

The original Keirsey Temperament Sorter was published in 1978 in Please Understand Me by David Keirsey and Marilyn Bates. The revised, enhanced Keirsey Temperament Sorter-II (KTS®-II) was introduced in 1998 in Keirsey’s follow-up work, Please Understand Me II: Temperament, Character, Intelligence.

Copyright and Commercial Licensing: The KTS®-II, its associated scoring keys, and registered trademarks (KTS®, Keirsey Temperament Sorter®) are the intellectual property of Prometheus Nemesis Book Company and Keirsey.com. While the 70 questions were published openly in the trade paperback editions of Please Understand Me II for self-administration, educational, and individual self-scoring purposes, commercial deployment, digital redistribution, automated software integration, corporate scoring, and institutional assessments require formal licensing and per-administration fee agreements through the copyright holders at Keirsey.com.

12. References

• Keirsey, D. (1998). Please understand me II: Temperament, character, intelligence. Prometheus Nemesis Book Company.
• Keirsey, D., & Bates, M. (1984). Please understand me: Character and temperament types (4th ed.). Prometheus Nemesis Book Company.
• Montgomery, S. (2002). People patterns: A modern guide to the four temperaments. Archer Publications.
• Quinn, M. T., Lewis, R. J., & Fischer, G. W. (1992). A cross-validation study of the Keirsey Temperament Sorter. Journal of Personality Assessment, 58(3), 590–599. https://doi.org/10.1207/s15327752jpa5803_14
• Tucker, I. F., & Gillespie, B. V. (1993). Correlations among the Keirsey Temperament Sorter, the Myers-Briggs Type Indicator, and the NEO Personality Inventory. Psychological Reports, 72(1), 115–120. https://doi.org/10.2466/pr0.1993.72.1.115
• Waskel, S. A. (1995). Temperament types: A comparison of the Keirsey Temperament Sorter and the Myers-Briggs Type Indicator. Psychological Reports, 76(2), 529–530. https://doi.org/10.2466/pr0.1995.76.2.529
• Kelly, K. R., & Jugovic, H. (2001). Concurrent validity of the Keirsey Temperament Sorter-II and the Myers-Briggs Type Indicator Form M. Career Development Quarterly, 49(4), 362–369. https://doi.org/10.1002/j.2161-0045.2001.tb00963.x

13. Items of the Scale (Questionnaire)