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Fulfilling the NPS Mission 101
Informal Visitor Contacts 102
Interpretive Talk 103
Conducted Activity 210
Interpretive Demonstration 220
Interpretive Writing 230
Curriculum-based Program 270
Planning Park Interpretation 310
Interpretive Media Development 311
Leaning Interpreters 330
Interpretive Research
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Planning Park Interpretation Curriculum-based Program Interpretive Writing Interp. Demonstration Conducted Activity Interpretive Talk Informal Visitor Contacts Fulfilling NPS Mission IDP Homepage Interp. Media Development Leading Interpreters Interp. Research Interpretive Writing Curriculum-based Program Planning Park Interpretation Interp. Media Development Leading Interpreters Interpretive Research Interp. Demonstration Conducted Activity Interpretive Talk Informal Visitor Contacts Fulfilling NPS Mission IDP Homepage





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Component for Module 101

How Interpretation Works: The Interpretive Equation

Content Outline| Resources | Suggested Developmental Activities

This component introduces the interpreter to the five basic elements of the interpretive process through the use of a formula known as the "interpretive equation."

Upon completion of this component the learner will be able to:

  • List the five basic elements of the interpretive equation and describe what they mean;

  • Explain how the various elements of the equation relate to one another;

  • Demonstrate how the elements of the equation relate to all interpretive planning, activities, programs and projects;

  • Apply the equation concepts to all subsequent interpretive activities.

The interpretive equation is a quick shorthand method that helps the learner remember basic concepts that relate to all interpretive activities. It is only a tool to assist interpretive approach. Whichever approach is used to present information, it is imperative that the learner thoroughly understands the five elements of the interpretive process and how they relate to actual interpretive work. Other models have been offered to convey similar concepts. ALL serve to support the interpreter in understanding basic relationships and the importance of key elements in being a successful, effective interpreter.

Because this component is meant to give interpreters a grounding in concepts that they will use throughout their career, it is recommended that many actual park examples illustrating the concepts be provided as part of the learning experience. This will enable the learner to gain experience in applying these somewhat abstract concepts to real-world situations and concerns.

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Content Outline:

I. The Interpretive Equation

A. (KR + KA) x AT = IO (Knowledge of the Resource + Knowledge of the Audience) x Appropriate Techniques = Interpretive Opportunities
1. The interpretive equation applies to all interpretive activities
2. It is important to keep the equation elements in balance

B. "Grading" or assessing the desired outcomes of the equation

1. The interpreter must regularly evaluate whether interpretive activities are providing effective interpretive opportunities (small "o" outcomes), and whether these opportunities result in the ultimate desired outcome of a stronger stewardship ethic in the audience (large "O" Outcomes).

II. The Five Elements of the Interpretive Equation

A. Knowledge of the Resource (KR)
1. Knowledge is more than just the facts about the resource. Interpreters must identify and be fully aware of the many different intangible and universal meanings the resources represent to various audiences.
2. Interpreters must possess a very broad knowledge of the history of the park beyond just the enabling legislation. They must be knowledgeable about past and contemporary issues, and the condition of the park and its resources.
3. Interpreters should not use their knowledge of the resources and the intangible/universal meanings associated with them to offer only bland recitals of non-controversial "safe" facts. Interpretation embraces a discussion of human values, conflicts, ideas, tragedies, achievements, ambiguities, and triumphs.
4. Interpreters must accommodate and present multiple points of view in their interpretation and not presume to expound what they think is the only "official" or "true" version of the resources and their meaning.
5. Interpreters must be careful to rely on accurate information when developing interpretive material and avoid the tendency to exaggerate or slant information to present a personal or particular viewpoint.
6. Interpreters should use their knowledge to convey the park's approved resource-related themes

B. Knowledge of the Audience (KA)

1. Important! The definition of audience includes more than just those individuals who actually visit a park. We have a professional responsibility to reach out and provide interpretive opportunities for those who will never visit a park, as well as to actual park visitors. There are many ways to be a visitor to a national park. One can visit a park in person, electronically via computer, through a program in a classroom, or by reading a book about the park.
2. There is no such thing as the average visitor.
3. Not every visitor requires an "intensive" interpretive experience.
4. Interpreters must recognize and respect the specific personal values and interests visitors associate with resources.
5. Interpreters should keep in mind the "visitors' bill of rights." Whether visiting a park on-site or off, visitors have a right to:
a) have their privacy and independence respected;
b) retain and express their own values;
c) be treated with courtesy and consideration;
d) receive accurate and balanced information.

6. Interpreters should recognize the "visitor continuum." The ultimate goal of interpretation is to provide opportunities for visitors to forge compelling linkages with the resources that they develop an active stewardship ethic. Visitors generally fall into a continuum in one of the following five categories, any of which may lead to increasing awareness of the relationships between tangible resources and their intangible and universal values:

a) recreation/"trophy hunting;"
b) nostalgia/refuge/isolation;
c) information/knowledge;
d) connections/linkages;
e) stewardship/patrons.

The interpreter's job is to ensure that visitors have a positive experience at any of these levels, and to try to help visitors reach a deeper and richer level of understanding if possible. No matter where the visitors are on the continuum, the interpreter should strive to give them something of value to take home.

C. Knowledge of Appropriate Techniques (AT)

1. There are many interpretive techniques, none of which is inherently better than any other. Determination of the appropriate technique results from analysis of the resource themes and audience profile. The interpreter should never choose a technique without first identifying the theme, goals, and objectives and the prospective audience to determine if it is an appropriate "fit." Choosing techniques willy-nilly or because the interpreter personally enjoys them may mean that programs are only reaching a small portion of the audience.
2. Whichever technique is chosen, whether personal or non-personal, on-site or off-site, interpreters should ensure that it addresses the tangible/intangible/universal linkages of the resource.
3. Interpreters must stay current on communications and delivery techniques and new media possibilities, and use them as appropriate. However, beware of adopting new techniques simply because they are new. See #1 above.
4. Interpreters must regularly evaluate the effectiveness of the techniques used, and replace and update them when they no longer achieve the desired outcomes.

D. The Interpretive Opportunity (IO)
1. To provide interpretive opportunities to the widest possible array of audiences, the interpreter must be proficient in as many techniques as possible, and should ensure that the overall park interpretive program offers the interpretive themes through as many different techniques as are appropriate.
2. The effect of the interpretive opportunity may not be immediately apparent to either the interpreter or the visitor. Interpretation may have both a long-term and/or a short-term effect. Interpreters should not always expect to see an immediate reaction in the visitor.

Interpretation is a seed, not a tree.
E. The Interpretive Outcome
1. Outcome evaluation must be visitor-based.
2. Evaluations should examine both short-term and long-term outcomes. Evaluations of short-term outcomes focus on whether an effective interpretive opportunity was offered to the audience (i.e., was the information correct, was an appropriate technique used). Evaluations of long-term outcomes focus on whether the larger NPS mission goals of perpetuating the nation's natural and cultural heritage and promoting a stewardship ethic in the public are met. (See Module 101 component "Why we do Interpretation, section I.)
3. Although outcome cannot always be measured immediately or quantitatively, the interpreter still has a professional responsibility to measure the effectiveness of the various interpretive opportunities being offered to the public to see if they are successful or need revising or updating.
4. Interpreters must seek feedback from the audience to gauge the effectiveness of the interpretive theme, content, program, etc. The degree to which the audience forms effective linkages to the resources, not the amount of information conveyed, audience applause, or the personal satisfaction of the interpreter, is the measure of an effective outcome.
5. Evaluation of interpretive outcomes can occur through a variety of mechanisms such as focus groups, visitor "report cards," and visitor surveys.

III. A Final Thought

Although not specifically included in the interpretive equation, the interpreter's attitude is a vital element in ensuring that the equation works properly. The interpreter must care about both the resource and facilitating interpretive opportunities and outcomes if he or she wishes to inspire caring in others. In short, those who appreciate resources protect them.

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Park legislative histories, records of Congressional hearings related to the park, records of public meetings, newspaper articles, local governmental, press, and community group archives. Current and historical park correspondence files. (These sources can provide good insights into how the public, particularly the local community, views the park and the types of values and meanings they associate with the resources.)

Clicking the Icon: Exploring the Meanings Visitors Attached to Three National Capital Memorials by Theresa L. Goldman, W. Jasmine Chen, and David L. Larsen. Journal of Interpretation Research. Volume 6, Number 1, 2001.
Part I
(PDF, 1295KB) Part II (998KB).

The Craft and Concepts of Interpretation: A Look at How National Park Service Interpreters Reveal and Facilitate Opportunities for Connections by W. Jasmine Chen. Doctoral dissertation, 2003. West Virginia University. [On-line]. Available.

The Interpretive Process Model, NPS Interpretive Development Program, 2002. The Interpretive Process Model provides a framework for the development of interpretive programs and products. It consists of a sequence of activities that guide an interpreter to develop opportunities for their audiences to make emotional and intellectual connections to the meanings of the resource, as well as cohesively develop an idea or ideas that are relevant to the resource and the audience.

Achieving Excellence in Interpretation: An Introduction to Compelling Stories, National Park Service, 1995. A workbook designed to help interpreters discover the compelling stories and intangible and universal meanings associated with the resources.

Interpretation for the 21st Century: Fifteen Guiding Principles for Interpreting Nature and Culture, Larry Beck and Ted Cable, Sagamore Publishing, 1998.

Interpreting Our Heritage, Freeman Tilden, University of North Carolina Press, 1957. Excellent discussion of the concepts represented by the interpretive equation.

Interpretive Skills Lesson Plans: "The Role of Interpretation in Park Operations" by Maria Gillett, 1992; "The Park-Visitor-Interpreter" by SER, 1983; "Identifying and Understanding the Visitor" by Linda Olson, 1983.

Interpretive Views: Opinions on Evaluating Interpretation in the National Park Service, Gary E. Machlis, ed., National Parks and Conservation Association, 1986. Collection of 24 essays by interpretive professionals on how to evaluate the effectiveness of the interpretive opportunity for visitors.

Islands of Hope, William Brown, National Recreation and Park Association, 1971.

On Interpretation: Sociology for Interpreters of Natural and Cultural History, Gary E. Machlis and Donald R. Field, eds., Oregon State University Press, 1992. Twenty essays discussing the wide variety of visitor needs and reactions to interpretation.

Personal Interpretation: Connecting Your Audience to Heritage Resources, Lisa Brochu and Tim Merriman, National Association for Interpretation, 2002. This book shares the traditions and trends of developing interpretive programs. Several elements of NPS IDP philosophy are discussed, including the tenets, interpretive equation, tangible-intangible links and universal concepts.

Personal Training Program for Interpreters, vintage 1976 NPS training package, available for loan from Mather Training Center.

Sacred Ground: Americans and Their Battlefields, Edward Linenthal, University of Illinois, l991. An intriguing look at some of the intangible meanings (religious, political, social, and personal) associated with American military sites. Includes chapters on Lexington, Concord, Gettysburg, Little Bighorn, and USS Arizona.

Sand County Almanac, Aldo Leopold, Oxford University Press, 1949. Includes a wonderfully personal account of how the author moved through a similar "visitor continuum," coming to recognize wildlife as more than a hunter's prey.

The Fifth Essence, Freeman Tilden, National Park Trust Fund Board, 1950. Short narrative exploring the intangible essence which makes parks unique.

The Past is a Foreign Country, David Lowenthal, Cambridge University Press, 1985. Excellent scholarly examination of what cultural resources represent to people and why. Full of examples from around the world. Particularly strong on exploring why people adopt a nostalgic view of history.

Focus Groups: A Tool for Evaluating Interpretive Services, Nancy Medlin and Gary Machlis, Cooperative Park Studies Unit, University of Idaho, l991. A videotape and manual, a practical step-by-step guide to evaluating interpretive services using the focus group technique.

Self-Critique: A Tool for Evaluating Interpretive Services, Nancy Medlin, Gary Machlis, and Jean McKendry, Cooperative Park Studies Unit, University of Idaho, 1993. A training video and manual on how an interpreter can assess the effectiveness of interpretive programs.

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Suggested Developmental Activities
1. Prepare a list of ten things you will try to do in the next two months to enrich the interpretation at the park and enhance your skills as an interpreter. Meet with your supervisor at the end of the two months to review the progress of your efforts and to prepare a new list for the next six months. Projects should not be part of assigned work duties, but small extra things which will help you to try out and evaluate ideas and concepts presented in the component.

2. Attend a Compelling Stories workshop or complete the Compelling Stories workbook.

3. Prepare material for the park's home page on the Internet which goes beyond information and explores the resource's intangible meanings for off-site visitors.

4. Begin a "life list" of interpretive techniques, observing others and recording what you think are the advantages and disadvantages of each.

5. Write your own personal contract for interpretation, describing your personal philosophy of interpretation and how you will strive to help others forge personal connections with the resources you interpret. If you have done this in the past, revisit your contract and consider its intent with this component in mind.

6. Actively participate in a Visitor Services Project or a visitors' focus group.

7. Review your park's entire interpretive program and try to determine at which level of the visitor continuum the programs and projects are aimed. Help the programs and projects if you find they are all aimed at one audience or if they are all aiming at levels below the "connections/linkages" step.

8. Review your park's interpretive programs and projects to see if they reveal, either directly or indirectly, some of the intangible and universal meanings associated with the resources. Help to enhance programs or projects which are weak.


Editor: STMA Training Manager Interpretation

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