Our motivation-based model of business rules is almost complete. By the time this column is published the model will have been through its final review within the Business Rules Group. It should be available on the Group’s website , with supporting documentation and examples, for general comment, criticism, and feedback.

Readers who have seen earlier editions of Dispatches will recall that this model has a business-oriented perspective (Zachman row 2) on business rules. Its driver is motivation (one of the six columns of the Zachman Framework), the rationale being that if an organization imposes business rules, it ought to be able to say "why."

The motivation-based model complements the Group’s earlier model, developed under the auspices of GUIDE, and last revised in October 1997. The earlier model has a system perspective (Zachman row 3) on business rules, and is focused particularly on rules that could be automated within the IT systems that support the organization.

Modeling Style

The motivation-based model looks different from the version shown in the last progress report in autumn 1999. First, we’ve changed the modeling style. We’ve opted for a simple notation of lines and nested boxes which, so far as we are aware, is not tied to any particular methodology, tool, or published standard.

• The Terms: Each box represents a concept (labeled with a "term"), which has a supporting description. Nesting indicates subtyping of concepts. Subtyping is generally exclusive -- for example, an instance of an End is a Vision, a Goal, or an Objective; it cannot be more than one of these -- but in a few areas, to keep the diagram simple, exclusivity is "mostly" rather than 100%.
• The Facts: Lines connecting boxes represent associations between concepts -- in other words, the "facts." In the spirit of a business rules approach, the default (unconstrained) interpretation is "many to many, optional." For example, an Influence may be judged in one or more Assessments, and an Assessment may be a judgment about one or more Influences.
• The Rules: The default interpretation of associations is the only one available from the diagram alone. More constrained definitions -- for example, that a Goal may amplify at most one Vision, an Impact Value is a characteristic of exactly one Assessment -- are provided in the supporting descriptions as "rule" statements.

Purpose

The purpose of the model is to explain the concepts, serving as a graphical overview of the underlying descriptions. We know already that some people, both inside and outside the Group, want to take it further; for example, to experiment with building a business rules repository based on the model and trying it on projects.

The model, as published, is not a logical design for this kind of development. However, between the diagram and the supporting documentation there is sufficient information that production of a more specific model using, say, UML, IDEF1X, Oracle, or MS Access conventions, should be straightforward.

Changes

We’ve also changed the shape of parts of the model. The core concepts -- ends and means, influences, policies and rules, enforcement, threats and opportunities, perceptions within the organization -- haven’t changed. They are part of the real world; they exist outside our model. What has happened is that, as we have developed more specific descriptions and tested them with examples, the mapping of our terms to the concepts has improved.

For example, we now have a better understanding of what a Business Policy is, than we had a few months ago. Then, it was a broadly-drawn concept that encompassed Mission, Strategy, Tactic, and Business Rule.

Now the concept is more precisely defined. Instances of Business Policy are developed inside the organization, motivated by Assessments of Influences as they relate to Ends and Means. The purpose of Business Policies is to guide the organization, particularly in the Strategies and Tactics that help the organization towards its Goals and Objectives. They may include, or be included in, other Business Policies. They don’t necessarily have to be formally or precisely defined -- precision and formality can be provided in the Business Rules derived from them.

As this definition of Business Policy was refined, so our view of Means (what Means means) expanded to become the broad concept that encompasses Mission, guidance, and approach.

The changes to the Means / Business Policy area of the model, especially the separation of guidance from approach and the changes in associations between concepts, are the most significant. Other changes address clarification and refinement.

Threat/Opportunity has become Assessment, and its subtypes have been extended to include Strength and Weakness as well as Threat and Opportunity. Within Impact Value (the quantitative part of an Assessment), Reward has become Potential Reward.

Influences, both Internal and External, have been more comprehensively defined, represented by their gaining of subtypes on the model. The External Influence formerly known as Market Condition has been expanded into Supplier, Customer, Competitor, and Partner influences.

Internal Influence has gained Infrastructure, Issue, Assumption, Habit, and Management Prerogative (sometimes things are required to be the way they are, just because management wants it so). Stated Value and Corporate Culture have been brought together as Stated and Unstated Corporate Value. The “Other” place-markers in both Internal and External Influence have been dropped.

Party (which had subtypes Organization and Person) has been replaced by Organization Component. As mentioned in the previous progress report, this is a placeholder for future development. However, we wanted to emphasize that in, for example, definition of Ends, establishment of Means, and recognition of Influence, what is important is the role that the person plays in the organization, and not the person as an individual.

Examples

As well as developing concept descriptions to support the model, we have been creating examples. Many of them are based on a (fictitious) car rentals company, EU-Rent, which we also used in the earlier report. Although there are individual examples drawn from other sources, EU-Rent provides at least one example of every concept, within the context of a single organization. This provides some coherence across the examples, and illustrates the relationships between many of the concepts.

The examples will be freely available to anyone who wants to use them, in training material, in help text in tools, in other publications, etc., provided that the Business Rules Group is credited as the source.

What Next?

After completion of the model, the Group will finalize its priorities for further development. A major area of interest is the extension of the motivation-based model into work practice. This has three aspects:

- workflow -- who does what, and when and where they do it;
- rule ownership and enforcement;
- performance assessment and improvement.

A related area is application of rules in different places. Another is management of rules over time. And there are more.

These are not independent areas of study. Workflow to accomplish the same ends may be different in different types of location. Management of rules over time is important to performance assessment and improvement, but addresses many other issues as well, such as response to changes in influences. We anticipate that we shall continue to find the Zachman Framework useful in defining and managing our work.

We also need to exploit the model, to work with other interested parties to apply its concepts in the business world, to realize it in tools, and to develop education and training material. And we need to collect feedback, and to record experience in its practical application.

We invite you to visit the Business Rule Group website , and let us know what you think.