The term "assessment center," connotes a location where one goes to be "assessed."  In truth, it is only a method, not a location. The method itself is basically a series of exercises where each participant is given an opportunity to demonstrate his or her skills to a group of skilled observers who carefully monitor the candidate’s behavior.  The observers are called "assessors."  Usually, the assessors are at least one to three ranks above the candidates.

However, a trained assessor need not actually be a higher rank, but must be thoroughly familiar with the assessment center method, the dimensions and behaviors required of the position being tested for and trained in observing and recording behavior.

Many of you recall being put through a variety of role-play scenarios in college, the Academy or in In-service training courses.  These are very similar, but the difference is in the dimensions that are being assessed. According to Pat Maher, President of "Personnel and Organization Development Consultants", in Southern California; "Assessors should adhere to the minimum professional standards as recommended by the International Congress of the Assessment Center Method." 

The key though, according to Maher, is that the foundation of the assessment center method is in the evaluation of recorded behavior. [1]

After extensive discussion as to the various dimensions the candidates demonstrated, the assessors rate the candidates.  Most trained professional assessors will go through a minimum of a three-day intensive training program prior to serving as an assessor. This is not always the case, as departments seek to cut costs, as assessment centers are not inexpensive! Unfortunately, this "cost savings" can be even more expensive when the wrong candidate is selected for the position when the selection is made from less objective methods!

Actually, there may be promotional exercises that are billed as

"assessment centers" but in fact are not true assessment centers.

The International Congress on the Assessment Center Method has established certain standards for assessment centers. 

These include:

Job Analysis

A job analysis of relevant behaviors must be conducted to determine the dimensions, competencies, attributes, and job performance indices important to job success in order to identify what should be evaluated by the assessment center.

Behavioral Classification

Behaviors displayed by participants must be classified into meaningful and relevant categories such as dimensions, attributes, characteristics, aptitudes, qualities, skills, abilities, competencies, and knowledge.

Assessment Techniques

The techniques used in the assessment center must be designed to provide information for evaluating the dimensions previously determined by the job analysis. Assessment center developers should establish a link from behaviors to competencies to exercises /assessment techniques. This linkage should be documented in a competency-by-exercise/assessment technique matrix.

Multiple Assessments

Multiple assessment techniques must be used. These can include tests, interviews, questionnaires, sociometric devices, and simulations. The assessment techniques are developed or chosen to elicit a variety of behaviors and information relevant to the selected competencies /dimensions.

Simulations

The assessment techniques must include a sufficient number of job-related simulations to allow opportunities to observe the candidate’s behavior related to each competency/dimension being assessed. At least one—and usually several—job-related simulations must be included in each assessment center. A simulation is an exercise or technique designed to elicit behaviors related to dimensions of performance on the job requiring the participants to respond behaviorally to situational stimuli. Examples of simulations include, but are not limited to, group exercises, in-basket exercises, interaction (interview) simulations, presentations, and fact-finding exercises. Stimuli may also be presented through video-based or virtual simulations delivered via computer, video, the Internet, or an intranet.

Assessors

Multiple assessors must be used to observe and evaluate each assessee. When selecting a group of assessors, consider characteristics such as diversity of race, ethnicity, age, sex, organizational level, and functional work area.

Assessor Training

Assessors must receive thorough training and demonstrate performance that meets the guidelines in the section, “Assessor Training,” prior to participating in an assessment center.

Recording Behavior

A systematic procedure must be used by assessors to record specific behavioral observations accurately at the time of observation. This procedure might include techniques such as handwritten notes, behavioral observation scales, or behavioral checklists. Audio and video recordings of behavior may be made and analyzed at a later date.

Reports

Assessors must prepare a report of the observations made during each exercise before the integration discussion or statistical integration.

Data Integration

The integration of behaviors must be based on a pooling of information from assessors or through a statistical integration process validated in accordance with professionally accepted standards.

Non-Assessment Center Activities

The following kinds of activities do not constitute an assessment center:

1. Assessment procedures that do not require the assessee to demonstrate

    overt behavioral responses are not behavioral simulations, and thus any

    assessment program that consists solely of such procedures is not an

    assessment center as defined herein. Examples of these are

    computerized in-baskets calling only for multiple-choice responses,

    situation interviews calling only for behavioral intentions, and written

    competency tests. Procedures not requiring an assessee to demonstrate

    overt behavioral responses may be used within an assessment center but

    must be coupled with at least one simulation requiring the overt display

    of behaviors.

2. Panel interviews or a series of sequential interviews as the sole

    technique.

3. Reliance on a single technique (regardless of whether it is a simulation)

    as the sole basis for evaluation. However, a single comprehensive

    assessment technique that includes distinct job-related segments (e.g., 

    large, complex simulations or virtual assessment centers with several

   definable components and with multiple opportunities for observations

   in different situations) is not precluded by this restriction.

4. Using only a test battery composed of a number of paper-and-pencil

    measures, regardless of whether the judgments are made by a statistical

    or judgmental pooling of scores.

5. Single-assessor evaluation (i.e., measurement by one individual using a

    variety of techniques such as paper-and-pencil tests, interviews,

    personality measures, or simulations).

6. The use of several simulations with more than one assessor but with no

    pooling of data (i.e., each assessor prepares a report on performance in

    an exercise, and the individual, unintegrated reports are used as the final

    product of the center).

7. A physical location labeled as an “assessment center” that does not

    conform to the methodological requirements noted above.

For the complete text of the Guidelines, refer to the assessment center.