Working Alliance Inventory

1. Abstract

The Working Alliance Inventory (WAI) is one of the most extensively utilized, empirically validated, and theoretically grounded psychometric instruments designed to evaluate the quality of the therapeutic relationship in counseling and psychotherapy. Developed by Adam O. Horvath and Leslie S. Greenberg in 1989, the WAI operationalizes Edward S. Bordin’s (1979) pantheoretical tripartite conceptualization of the therapeutic alliance. The instrument captures three interdependent dimensions: Goal (mutual agreement on and endorsement of the primary targets, objectives, and desired outcomes of the therapeutic intervention), Task (concordance regarding the specific behaviors, in-session activities, interventions, and responsibilities expected of both client and therapist), and Bond (the interpersonal affective network of mutual trust, genuine acceptance, personal liking, and reciprocal respect that unites the dyad). Originally constructed as a comprehensive 36-item self-report questionnaire, the WAI provides parallel versions for both client (WAI-C) and therapist (WAI-T) perspectives, alongside validated observer-rated formats (WAI-O) and subsequent abbreviated iterations such as the 12-item Working Alliance Inventory – Short Revised (WAI-SR).

Items on the original 36-item inventory are evaluated using a 7-point Likert scale ranging from 1 (Never) to 7 (Always), with balanced negatively keyed items designed to control for acquiescence response bias. Extensive psychometric literature reveals exceptional internal consistency across clinical and non-clinical cohorts, with Cronbach’s alpha coefficients routinely exceeding .90 for the composite alliance score and ranging from .80 to .93 across individual subscales. Test-retest reliability across early, middle, and late treatment phases demonstrates high stability, while structural equation modeling and exploratory and confirmatory factor analyses support both a three-factor correlated model and a hierarchical bifactor structure characterized by a dominant general alliance factor. Crucially, the WAI serves as a premier predictor of psychotherapy retention, symptom reduction, and clinical outcome across cognitive-behavioral, psychodynamic, humanistic, and integrative treatment modalities, solidifying its standing as an indispensable assessment tool in contemporary clinical psychology and psychotherapy research.

2. Keywords

Working Alliance Inventory, WAI, therapeutic alliance, Edward Bordin, psychotherapy outcome, clinical assessment, Task-Goal-Bond, psychometrics, psychotherapy research, counselor-client relationship, WAI-SR, interpersonal process

3. Authors

The Working Alliance Inventory was created by Adam O. Horvath, Ed.D., and Leslie S. Greenberg, Ph.D.

• Adam O. Horvath, Ed.D.: Professor Emeritus of Counseling Psychology at Simon Fraser University, Burnaby, British Columbia, Canada. Dr. Horvath is an internationally acknowledged authority on the therapeutic relationship, alliance rupture and repair processes, and the comparative methodology of psychotherapy research. Contact: [email protected]. Official repository: http://wai.profhorvath.com/.
• Leslie S. Greenberg, Ph.D.: Distinguished Research Professor Emeritus of Psychology at York University, Toronto, Ontario, Canada. Dr. Greenberg is one of the primary originators of Emotion-Focused Therapy (EFT) and an influential figure in process-experiential therapies, empathy research, and therapeutic change mechanisms.

4. Purpose

The principal objective of the Working Alliance Inventory is to systematically measure the quality, strength, and therapeutic viability of the collaborative relationship between client and practitioner, independent of theoretical orientation. Prior to the development of the WAI, existing clinical measures of the therapeutic relationship were heavily entrenched in traditional psychoanalytic paradigms (e.g., transference, countertransference, and ego-analytic resistance constructs) or client-centered humanistic models (such as Rogers’ core conditions of empathy, congruence, and unconditional positive regard). While conceptually profound, these early measurements lacked universal applicability across emerging modalities such as cognitive-behavioral therapy, systemic family therapy, and brief strategic interventions. The WAI was deliberately constructed to transcend parochial theoretical boundaries by providing a common, pantheoretical metric capable of quantifying the functional working relationship across disparate clinical settings.

In clinical practice, the WAI fulfills multiple diagnostic, process-monitoring, and quality-assurance functions. Administered early in the treatment trajectory—typically between sessions three and five—the inventory establishes an empirical baseline of relational cohesion. This early administration is critical because empirical research demonstrates that the alliance established within the first few sessions accounts for the greatest variance in treatment adherence, premature drop-out prevention, and ultimate symptom alleviation. Regular or episodic reassessment enables practitioners to monitor longitudinal alliance dynamics, identify subtle relationship strains, and detect covert alliance ruptures before they culminate in treatment failure. Furthermore, parallel administration to both client and therapist illuminates perceptual divergences; discrepancies where the therapist overestimates or underestimates the client’s perceived bond or agreement on therapeutic tasks provide vital clinical material for collaborative meta-communication and recalibration of the treatment plan.

In empirical psychotherapy research, the WAI functions as an essential standard instrument for clinical trials, process-outcome designs, and comparative effectiveness studies. It serves as a primary independent variable or mediator in structural equation models examining the mechanisms through which therapeutic interventions achieve efficacy. Investigators utilize the WAI to control for relational common factors when testing specific theoretical techniques, to evaluate the relational competencies of clinicians across supervisory training programs, and to investigate cross-cultural variations in collaborative healing dynamics. Its rigorous psychometric properties make it the benchmark against which newer relationship instruments and digital mental health alliances (e.g., therapeutic bonds formed with conversational AI agents and digital therapeutics) are evaluated.

5. Psychological Construct

The psychological construct evaluated by the Working Alliance Inventory is the working alliance, conceptualized not merely as affective warmth or passive compliance, but as an active, purposive collaboration between a help-seeker and a designated change agent. Horvath and Greenberg (1989) adopted and refined Edward S. Bordin’s (1979) tripartite structural paradigm, positing that an optimal therapeutic relationship comprises three distinct yet reciprocally reinforcing subconstructs: Tasks, Goals, and Bonds.

Task Dimension

The Task dimension denotes the degree of mutual agreement, cognitive clarity, and shared endorsement concerning the specific in-session activities, behavioral exercises, homework assignments, and procedural techniques that constitute the substance of therapy. In a functional alliance, the client perceives the assigned or negotiated tasks as viable, relevant, meaningful, and directly linked to their psychological difficulties, while the therapist communicates the clinical rationale underlying these activities with clarity. For example, in cognitive restructuring, exposure hierarchies, or somatic exploration, high Task alignment occurs when the client understands what is expected of them and believes these activities will lead to meaningful personal transformation (e.g., Item 16: “I feel that the things I do in therapy will help me to accomplish the changes that I want”). Conversely, task deficits manifest as confusion, ideological friction regarding interventions, skepticism regarding therapeutic procedures, or resentment toward prescriptive demands (e.g., Item 33: “The things that _____ is asking me to do don’t make sense”).

Goal Dimension

The Goal dimension captures the extent to which the client and therapist formulate, endorse, and maintain shared commitments to the ultimate objectives, targets, and desired outcomes of the therapeutic intervention. Rather than reflecting unilateral therapist-imposed objectives or unexamined client wishes, the Goal dimension reflects a negotiated consensus regarding what the therapy is designed to accomplish, whether symptom mitigation, structural personality change, identity consolidation, existential exploration, or interpersonal skill acquisition. Elevated scores reflect profound mutual understanding of both immediate and long-range targets (e.g., Item 22: “_____ and I are working towards mutually agreed upon goals”). Low Goal alignment is characterized by covert or overt disagreements regarding the focus of therapy, discrepancies in diagnostic prioritization, or ambiguity regarding the criteria for successful termination (e.g., Item 10: “I disagree with _____ about what I ought to get out of therapy”).

Bond Dimension

The Bond dimension encompasses the multifaceted affective network of personal attachments, mutual trust, unfeigned respect, empathic resonance, and shared appreciation existing between client and therapist. Rooted in human attachment theory and Rogerian humanistic psychology, the Bond dimension delineates the relational safety necessary for clients to confront distressing, shame-inducing, or traumatizing psychological material. High Bond scores signify that the client experiences the therapist as genuinely caring, accepting, non-judgmental, and dependable (e.g., Item 17: “I believe _____ is genuinely concerned for my welfare”; Item 36: “I feel _____ cares about me even when I do things that he/she does not approve of”). A compromised Bond dimension is signaled by interpersonal alienation, fear of rejection or abandonment (e.g., Item 29: “I have the feeling that if I say or do the wrong things, _____ will stop working with me”), guardedness, or emotional aloofness.

6. Theoretical Framework

The conceptual foundation of the Working Alliance Inventory rests squarely upon Edward S. Bordin’s (1979) seminal paper, “The Generalizability of the Psychoanalytic Concept of the Working Alliance.” To contextualize Bordin’s contributions, one must trace the historical evolution of the alliance construct from early psychodynamic formulations to pantheoretical models.

Historical Evolution

Sigmund Freud initially observed that successful psychoanalysis required the patient to develop an affectionate, uninhibited attachment to the analyst, distinguishing this realistic collaboration from irrational transference projections. Subsequently, Richard Sterba (1934) described the “ego alliance,” focusing on how the patient’s rational ego aligns with the observing ego of the analyst. Ralph Greenson (1965, 1967) expanded this into the “working alliance,” emphasizing the patient’s capacity to cooperate purposefully in the analytical tasks despite fluctuating transference neuroses. Concurrently, Carl Rogers (1957) and the humanistic tradition posited that the relational conditions of congruence, unconditional positive regard, and accurate empathy were not merely adjunctive, but were necessary and sufficient conditions for therapeutic change.

Bordin’s Pantheoretical Synthesis

Recognizing the limitations of tying the alliance exclusively to psychodynamic transference analysis or humanistic relational conditions, Bordin proposed that a working alliance is present in all successful change-inducing relationships, including counseling, teaching, medical care, and mentorship. Bordin posited that the alliance is constituted by three dynamic, interacting components:

1. Collaborative Tasks: The explicit and implicit demands made upon the client and change agent during the intervention process. Different psychotherapy paradigms mandate distinct tasks (e.g., free association and dream analysis in psychoanalysis; thought recording and behavioral experimentation in cognitive therapy; two-chair dialogues in gestalt therapy). The alliance depends not on the specific theoretical nature of these tasks, but on whether the dyad forms a shared cognitive agreement regarding their therapeutic validity.
2. Negotiated Goals: The directional targets toward which treatment is oriented. The strength of the alliance relies on the dyad’s continuous calibration of these objectives, balancing client self-determination with clinician assessment.
3. Interpersonal Bonds: The socio-emotional matrix characterized by reciprocal esteem, liking, security, and mutual investment. Strong bonds allow the therapeutic pair to weather inevitable clinical frustrations, misunderstandings, and painful emotional disclosures without collaborative breakdown.

Horvath and Greenberg (1989) operationalized Bordin’s theoretical principles into psychometric items by formulating balanced declarative statements reflecting each of the three dimensions. Their framework assumes that the alliance is an emergent property of the dyad, continually co-constructed and renegotiated over time. Furthermore, the model presumes that while Tasks, Goals, and Bonds are conceptually differentiated, they function synergistically: mutual agreement on tasks deepens mutual trust (Bond), while a robust affective bond facilitates willingness to engage in challenging or anxiety-provoking therapeutic activities (Tasks) toward shared aims (Goals).

7. Validity

The Working Alliance Inventory has undergone exhaustive validation across diverse clinical populations, diagnostic presentations, cultural backgrounds, and therapeutic modalities. Its psychometric validity is evidenced across multiple empirical domains:

Construct and Convergent Validity

Construct validity was initially established by Horvath and Greenberg (1989) through rigorous item-generation pipelines involving theoretical experts and subsequent convergent testing against pre-existing relationship measures. The WAI total and subscale scores correlate strongly with alternative alliance metrics, such as the Helping Alliance Questionnaire (HAQ; Alexander & Luborsky, 1986; r = .68 to .84), the California Psychotherapy Alliance Scale (CALPAS; Gaston, 1991; r = .72 to .89), and the Penn Helping Alliance Rating Scale (Penn; Morgan et al., 1982). Furthermore, convergent validity is documented through significant positive associations with measures of therapist empathy (such as the Barrett-Lennard Relationship Inventory; BLRI) and client perceptions of clinician social influence attributes (attractiveness, trustworthiness, expertness; Anderson, 2008).

Predictive and Outcome Validity

The defining strength of the WAI resides in its predictive validity regarding psychotherapy outcomes. In their landmark meta-analysis, Horvath and Symonds (1991) examined 24 studies and discovered an overall effect size of r = .26 between alliance and outcome, establishing that the working alliance accounts for substantial variance in therapy success across theoretical orientations. Subsequent large-scale meta-analyses (e.g., Martin, Garske, & Davis, 2000; Horvath, Del Re, Flückiger, & Symonds, 2011; Flückiger, Del Re, Wampold, & Horvath, 2018) encompassing hundreds of studies and tens of thousands of patients confirmed that the alliance-outcome correlation remains robust (weighted average correlation r ≈ .28 to .31, equivalent to d ≈ .57 to .65), independent of whether outcome is operationalized as symptom reduction (e.g., Beck Depression Inventory, SCL-90-R), functional recovery, or interpersonal improvements. Research consistently reveals that client ratings of the alliance on the WAI possess higher predictive power for therapeutic outcome than therapist ratings, highlighting the supremacy of the client’s subjective experience in driving therapeutic gains.

Discriminant and Incremental Validity

Discriminant validity has been demonstrated by showing that early WAI scores remain distinct from early symptomatic distress levels or passive acquiescence. While patients presenting with severe personality pathology or attachment insecurity occasionally register lower baseline alliance scores, longitudinal path analyses confirm that WAI scores predict mid-treatment and post-treatment gains even after statistically partialling out initial symptom severity and temporal symptom improvements (pre-alliance gain control). Additionally, Busseri and Tyler (2003) demonstrated that the WAI differentiates the specific relational alliance from general social support, establishing that the instrument evaluates a distinct professional collaboration rather than an ordinary friendship.

8. Reliability

The Working Alliance Inventory exhibits robust psychometric reliability across its complete, short, and observer variations:

Internal Consistency

In the original validation study by Horvath and Greenberg (1989), the 36-item Client Form (WAI-C) yielded a total composite internal consistency reliability coefficient (Cronbach’s alpha) of .93. The individual subscales demonstrated strong reliability:

• Task Subscale: α = .89 to .92
• Bond Subscale: α = .85 to .88
• Goal Subscale: α = .87 to .89

Parallel analyses on the Therapist Form (WAI-T) yielded an overall alpha of .91, with subscale alphas ranging from .82 to .90. In a comprehensive reliability generalization study synthesizing data across 109 studies, Hanson, Curry, and Bandalos (2002) confirmed that the average internal consistency across published investigations was .92 for the full scale, .86 for Task, .84 for Bond, and .86 for Goal. For the abbreviated 12-item Working Alliance Inventory – Short Revised (WAI-SR; Hatcher & Barends, 1996; Tracey & Kokotovic, 1989), Cronbach’s alphas remain consistently high, typically ranging between .88 and .94 for the total scale and between .79 and .91 for the individual 4-item subscales.

Test-Retest Stability and Dynamic Sensitivity

Test-retest reliability assessments conducted across short intervals (e.g., between consecutive sessions during stable phases of treatment, such as sessions 3 and 4) yield temporal stability coefficients ranging from r = .78 to .88 (Horvath & Greenberg, 1989; Tracey & Kokotovic, 1989). However, because the working alliance is fundamentally a dynamic, evolving process construct subject to alliance ruptures, developmental plateaus, and reparative breakthroughs, longitudinal coefficients across distal points in therapy (e.g., session 3 to session 15) appropriately moderate to r = .55 to .70. This moderate longitudinal correlation underscores the instrument’s sensitivity to real relational changes over the course of treatment rather than rigid trait-like immutability.

9. Factor Analysis

The structural composition of the Working Alliance Inventory has been the subject of extensive psychometric investigation, sparking meaningful structural modeling dialogues within clinical measurement literature.

Exploratory Factor Analysis (EFA)

In the original instrument development, Horvath and Greenberg (1989) utilized item selection procedures grounded in rational-theoretical sorting by expert judges, retaining 36 items (12 per dimension) that best demonstrated conceptual fidelity and distinct factor loadings. However, initial exploratory factor analyses frequently yielded an overarching, undifferentiated factor accounting for between 45% and 60% of the total variance, upon which nearly all items loaded significantly. This elevated shared variance occurs because in successful therapy, clients rarely draw rigid psychological distinctions between liking their therapist (Bond), agreeing on what to work on (Goal), and engaging in clinical techniques (Task).

Confirmatory Factor Analysis (CFA) and Bifactor Structures

Tracey and Kokotovic (1989) performed rigorous confirmatory factor analyses on the 36-item WAI across multiple therapeutic cohorts to test competing structural models. Their investigations contrasted a one-factor unidimensional model, a three-factor oblique model (Bordin’s original Task, Goal, and Bond), and a hierarchical bifactor model. The findings revealed that while the three-factor model yielded adequate fit, a hierarchical structure comprising one general “General Alliance” factor alongside three distinct nested primary factors (Tasks, Goals, and Bonds) demonstrated superior statistical fit (CFI > .92, TLI > .90, RMSEA ≈ .058).

Subsequent psychometric examinations (e.g., Busseri & Tyler, 2003; Falkenström, Granström, & Holmqvist, 2013) evaluating both the 36-item long form and the 12-item short forms (WAI-S and WAI-SR) have supported this bifactor structure. In these models, the general alliance factor accounts for the vast majority of predictive variance regarding ultimate clinical outcomes (symptom reduction), whereas the specific Task, Goal, and Bond factors explain unique variance relevant to specific process variables. For instance, specific Task discrepancies predict drop-out risk, while Bond variance correlates uniquely with attachment orientation and interpersonal trust dimensions.

10. Instrument / Measurement Tool

• Formal Instrument Name: Working Alliance Inventory (WAI)
• Alternative Titles & Variations:
  • WAI Long Form – Client (WAI-C; 36 items)
  • WAI Long Form – Therapist (WAI-T; 36 items)
  • WAI Observer-Rated Form (WAI-O; 36 items)
  • Working Alliance Inventory – Short Form (WAI-S; 12 items; Tracey & Kokotovic, 1989)
  • Working Alliance Inventory – Short Revised (WAI-SR; 12 items; Hatcher & Barends, 1996)
• Target Population: Adolescents and adults (ages 16+) undergoing individual psychological counseling or psychotherapy across outpatient, inpatient, or community clinical settings.
• Administration Modality: Self-report questionnaire (paper-and-pencil or secure digital delivery).
• Completion Duration:
  • Full 36-item form: Approximately 10 to 15 minutes.
  • 12-item short forms: Approximately 3 to 5 minutes.
• Response Scale: 7-point Likert scale:
  • 1 = Never
  • 2 = Rarely
  • 3 = Occasionally
  • 4 = Sometimes
  • 5 = Often
  • 6 = Very Often
  • 7 = Always
• Dimensional Structure & Item Allotment (Full 36-item WAI):
  • Task Scale (12 items): Items 2, 4, 7*, 11*, 13, 15*, 16, 18, 24, 31*, 33*, 35
  • Bond Scale (12 items): Items 1*, 5, 8, 17, 19, 20*, 21, 23, 26, 28, 29*, 36
  • Goal Scale (12 items): Items 3*, 6, 9*, 10*, 12*, 14, 22, 25, 27*, 30, 32, 34*
  • Note: Asterisks (*) denote items that must be reverse-scored prior to calculating scale totals.
• Scoring and Computational Rules:
  1. Reverse Scoring: Reverse the numerical score of the 14 negatively phrased items (Items 1, 3, 7, 9, 10, 11, 12, 15, 20, 27, 29, 31, 33, 34) according to the transformation rule: Transformed Score = 8 - Original Score (i.e., 1 becomes 7, 2 becomes 6, 3 becomes 5, 4 remains 4, 5 becomes 3, 6 becomes 2, and 7 becomes 1).
  2. Subscale Scores: Sum the scored and reverse-scored items within each respective domain:
     • Task Score = ∑(Items 2, 4, 7*, 11*, 13, 15*, 16, 18, 24, 31*, 33*, 35) (Range: 12–84)
     • Bond Score = ∑(Items 1*, 5, 8, 17, 19, 20*, 21, 23, 26, 28, 29*, 36) (Range: 12–84)
     • Goal Score = ∑(Items 3*, 6, 9*, 10*, 12*, 14, 22, 25, 27*, 30, 32, 34*) (Range: 12–84)
  3. Composite Total Alliance Score: Sum all 36 items: Total WAI = Task + Bond + Goal (Range: 36–252). Alternatively, mean subscale and mean total scores may be reported on the original 1 to 7 continuum by dividing scale sums by 12 and the composite sum by 36. Higher scores reflect a stronger, more coherent therapeutic alliance.

11. Permissions & Fee and Test Year

The Working Alliance Inventory was formally published in 1989 by Adam O. Horvath and Leslie S. Greenberg in the Journal of Counseling Psychology. Dr. Adam O. Horvath maintains copyright over the original instruments while granting open, fee-free permission for clinical, educational, non-commercial, and academic research applications, provided that proper bibliographic citation is accorded to the foundational publications.

Prospective investigators and mental health practitioners may freely access, download, and utilize the various language translations and authorized derivatives (Client, Therapist, Observer, Short, and Short-Revised formats) through Dr. Horvath’s official academic repository at http://wai.profhorvath.com/. Commercial software vendors or clinical service platforms seeking to integrate the WAI into proprietary for-profit electronic health record (EHR) systems must obtain explicit written authorization by contacting the primary author via email ([email protected]).

12. References

• Anderson, R. S. (2008). Counselor gender self-confidence and social influence in counseling: Counselor perceptions of the therapeutic alliance (Doctoral dissertation, Ohio University). OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1213038628
• Bordin, E. S. (1979). The generalizability of the psychoanalytic concept of the working alliance. Psychotherapy: Theory, Research & Practice, 16(3), 252–260. https://doi.org/10.1037/h0085885
• Busseri, M. A., & Tyler, J. D. (2003). Interchangeability of the Working Alliance Inventory and Working Alliance Inventory–Short Form. Psychological Assessment, 15(2), 193–197. https://doi.org/10.1037/1040-3590.15.2.193
• Falkenström, F., Granström, F., & Holmqvist, R. (2013). Measurement properties of the Working Alliance Inventory Short Form Revised. Psychological Assessment, 25(2), 390–402. https://doi.org/10.1037/a0031301
• Flückiger, C., Del Re, A. C., Wampold, B. E., & Horvath, A. O. (2018). The alliance in adult psychotherapy: A meta-analytic synthesis. Psychotherapy, 55(4), 316–340. https://doi.org/10.1037/pst0000172
• Gaston, L. (1991). Reliability and criterion-related validity of the California Psychotherapy Alliance Scales—Patient version. Psychological Assessment: A Journal of Consulting and Clinical Psychology, 3(1), 68–74. https://doi.org/10.1037/1040-3590.3.1.68
• Greenson, R. R. (1965). The working alliance and the transference neurosis. The Psychoanalytic Quarterly, 34(2), 155–181. https://doi.org/10.1080/21674086.1965.11927405
• Hanson, W. E., Curry, K. T., & Bandalos, D. L. (2002). Reliability generalization of Working Alliance Inventory scale scores. Educational and Psychological Measurement, 62(4), 659–673. https://doi.org/10.1177/0013164402062004008
• Hatcher, R. L., & Barends, A. W. (1996). Patients’ view of the alliance in psychotherapy: Exploratory factor analysis of three alliance measures. Journal of Consulting and Clinical Psychology, 64(6), 1326–1336. https://doi.org/10.1037/0022-006X.64.6.1326
• Horvath, A. O., Del Re, A. C., Flückiger, C., & Symonds, D. (2011). Alliance in individual psychotherapy. Psychotherapy, 48(1), 9–16. https://doi.org/10.1037/a0022186
• Horvath, A. O., & Greenberg, L. S. (1989). Development and validation of the Working Alliance Inventory. Journal of Counseling Psychology, 36(2), 223–233. https://doi.org/10.1037/0022-0167.36.2.223
• Horvath, A. O., & Symonds, B. D. (1991). Relation between working alliance and outcome in psychotherapy: A meta-analysis. Journal of Counseling Psychology, 38(2), 139–149. https://doi.org/10.1037/0022-0167.38.2.139
• Martin, D. J., Garske, J. P., & Davis, M. K. (2000). Relation of the therapeutic alliance with outcome and other variables: A meta-analytic review. Journal of Consulting and Clinical Psychology, 68(3), 438–450. https://doi.org/10.1037/0022-006X.68.3.438
• Rogers, C. R. (1957). The necessary and sufficient conditions of therapeutic personality change. Journal of Consulting Psychology, 21(2), 95–103. https://doi.org/10.1037/h0045357
• Tracey, T. J., & Kokotovic, A. M. (1989). Factor structure of the Working Alliance Inventory. Psychological Assessment: A Journal of Consulting and Clinical Psychology, 1(3), 207–210. https://doi.org/10.1037/1040-3590.1.3.207

13. Items of the Scale (Questionnaire)