What s in the BRG s Business Rules Manifesto

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1 What s in the BRG s Business Rules Manifesto POLICY 2003 Ronald G. Ross Principal, Business Rule Solutions, LLC Executive Editor, Business Rules Journal Reference: Principles of the Business Rule Approach Ronald G. Ross, Addison-Wesley, Available via Business Rules Manifesto The Principles of Rule Independence by Business Rules Group Version 1.3, April 28,

2 About Ronald G. Ross Ronald G. Ross is Co-Founder and Principal of Business Rule Solutions, LLC ( provides workshops, consulting services, publications, and methodology supporting business analysis, business rules, and rule management. At, Mr. Ross co-develops Proteus TM, its landmark business rules methodology, which features numerous innovative business rule techniques including the popular RuleSpeak (available free through These are the latest offerings in a 30-year career that has consistently featured creative, business-driven solutions. Mr. Ross also serves as Executive Editor of and its flagship on-line publication, Business Rules Journal. He is a regular columnist for the Journal s Commentary section which also features John Zachman, Chris Date and Terry Halpin. BRCommunity.com, hosted and sponsored by, is a vertical community for professionals working with business rules and related areas. Mr. Ross was formerly Editor of the Data Base Newsletter from 1977 to Mr. Ross is recognized as the father of business rules. He serves as Co-Chair of the Business Rule Forum Conference. He was a charter member of the Business Rules Group in the 1980s, and was a co-editor of its watershed 2000 paper, Organizing Business Plans: The Standard Model for Business Rule Motivation. He is also active in the OMG Business Rules SIG. Mr. Ross is the author of a half-dozen professional books. His newest work, Principles of the Business Rule Approach, has just been released by Addison-Wesley (2003). Other recent books on business rules include Business Rule Concepts (1998) which provides an easy-to-read, non-technical explanation of business rules, and The Business Rule Book (Second Edition, 1997) which presents a new and revolutionary approach to categorizing and modeling business rules in declarative form. Mr. Ross received his M.S. in information science from Illinois Institute of Technology, and his B.A. from Rice University. 2

3 About the Business Rules Manifesto Purpose To provide a clear statement of the business rule message as the Business Rules Group (BRG) sees it. To declare independence for rules in the world of requirements and models. To signal the birth of a new, revolutionary kind of business architecture and IT platform. 3

4 About the Business Rules Manifesto A Brief Background A 2002 work product of the BRG. Version 1.0 completed in January, Each item approved by unanimous(!) vote. Submitted as part of the BRG s OMG BR SIG RFI response in January, Presented to the OMG BR SIG in Feb, Version 1.3 prepared for this Conference, to obtain feedback and reaction. A final version 2.0 planned for release at the November Business Rules Forum Conference 2003, in Nashville, TN, USA. 4

5 About the Business Rules Manifesto Notes Available via May be reproduced freely with BRG s copyright and publication notice included (see below). Feedback Welcome! (Feedback will be discussed in the BRG s June Zurich meeting.) Caveat Although not definitive with respect to architecture, the BRG intends this document to prescribe a class of platform that has distinctive rule-oriented features. Copyright, Business Rules Group. Edited by Ronald G. Ross. Permission is granted for unlimited reproduction and distribution of this document under the following conditions: (a) The copyright and this permission notice are clearly included. (b) The work is clearly credited to the Business Rules Group. (c) No part of the document, including title, content, copyright, and permission notice, is altered, abridged or extended in any manner. 5

6 About the Business Rules Manifesto A Business Rule......is a statement that defines or constrains some aspect of the business....is intended to assert business structure, or to control or influence the behavior of the business....cannot be broken down or decomposed further into more detailed business rules....if reduced any further, there would be loss of important information about the business. Reference: Defining Business Rules ~ What Are They Really? (formerly known as the GUIDE Business Rules Project Final Report, November 1995), Business Rules Group, (3rd Ed.), July Available on 6

7 About the Business Rules Manifesto Basic Assumptions 1.1. Rules are a first-class citizen of the requirements world Rules are essential for, and a discrete part, of business models and technology models Rules are explicit constraints on behavior and/or provide support to behavior Rules are not process and not procedure. They should not be contained in either of these Rules apply across processes and procedures. There should be one cohesive body of rules, enforced consistently across all relevant areas of business activity. Business rules depend on no other kind of model or deliverable to exist. When they are shown to have such dependence, you are assuming a class of platform. 7

8 About the Business Rules Manifesto Business Implications 8.1. Business rules are a vital business asset In the long run, rules are more important to the business than hardware/software platforms Rules should be managed in such a way that they can be readily re-deployed to new hardware/software platforms Rules, and the ability to change them effectively, are fundamental to improving business adaptability. Rules should be externalized so the business side can manage them directly! Reduce IT Involvement Establish Traceability Maintain Control 8

9 About the Business Rules Manifesto Supporting Business People 7.1. Rules should arise from knowledgeable business people Business people should have tools available to help them formulate and manage rules. Business Rule Methodology is truly Business-Driven! 7.3. Business people should have tools available to help them verify business rules against each other for consistency. 9

10 About the Business Rules Manifesto Business Motivation Rules have a business context and motivation Rules are about business practice and guidance; therefore, rules are motivated by business goals and objectives and are shaped by various influences Rules always cost the business something The cost of rule enforcement must be balanced against business risks and against business opportunities that might otherwise be lost More rules is not better. Usually fewer good rules is better. There are no free lunches with respect to rules. Core business rules (or policies or governing rules) are the cutting edge of business plans An effective system can be based on a small number of rules. Additional, more discriminating rules can be subsequently added, such that over time the system becomes smarter. 10

11 The BRG Motivation Model Organizing Business Strategy The Standard Model for Business Rule Motivation by the Business Rules Group A business rule is a directive that is intended to influence or guide business behavior. Such directives exist in support of business policy, which is formulated in response to risks, threats or opportunities. 11

12 Proteus TM The Policy Charter Auto Insurance Sample Policy Charter (segment) Auto Insurance Ensure cost-efficient operations Provide efficient customer service Support an efficient Collision Repair Industry Maintain a close relationship with Collision Repair Industry Repair and claims data should be transferred electronically to the Collision Repair Industry Expectation that the corporation will maintain infrastructure at the body shops Road estimators will use dial up to access claims information Body shops should be reponsible for their own systems and infrastructures Reference: Business Knowledge -- Packaged in a Policy Charter, by Gladys S.W. Lam, May/June, Available on Dial-up access is not available at the body shop Dedicated line for dial-up must be part of accrediation package 12

13 Using the Reductionist Approach to Rules Governing Rule: The XYZ Health Program has a cost share policy. Clients are responsible for the payment of 25% of the cost of the benefit(s) to a maximum contribution of $500 per family per benefit year. Operating Rules: 11.1 Maximum contribution per family per benefit year must be set to $ Benefit year must be July 1 June Client fee portion for a claim must be computed as 25% of the claim amount, if contribution per family per benefit year does not exceed maximum contribution per family per benefit year Client fee portion for a claim must be set to $0, if contribution per family per benefit year exceeds maximum contribution per family per benefit year. 13

14 About the Business Rules Manifesto The Knowledge Assumption 2.1. Rules build on facts, and facts build on concepts as expressed by terms Terms express business concepts; facts make assertions about these concepts; rules constrain and support these facts Rules must be explicit. No rule is ever assumed about any concept or fact unless a rule has been specified explicitly Rules are basic to what the business knows about itself that is, to basic business knowledge. Rules need to be nurtured, protected, and managed. Business logic is built in building-block fashion. Business rules express basic business knowledge. Reference: Principles of the Business Rule Approach, Chapter 5. 14

15 Proteus TM Fact Model is used to check-out Library Fact Model holds library card borrower is authorized for is charged against librarian makes works for library owns is owned by A Business Rule is one and only one of the following... Term typically 100s Fact borrower type person organization assessment is made for book typically 10X Terms Rule typically 10X Facts fee amount Rule: A library card may be used to check-out a book only if the book is owned by a library for which the card is authorized. Legend = Term (+ Definition) = Fact = Category 15

16 About the Business Rules Manifesto Expressing Rules 3.1. Rules should be expressed declaratively for the business audience, in naturallanguage sentences. If something cannot be expressed, then it is not a rule Business rules should be expressed in such a way that they can be validated for correctness by business people A rule is distinct from any enforcement defined for it. These are separate concerns. The practical side of declarative A business language for rules. Example: RuleSpeak TM 3.4. Rules should be defined independently of responsibility for the who, w h e r e, w h e n, or h o w of their enforcement Exceptions to rules are expressed by other rules Business rules should be expressed in such a way that they can be verified against each other for consistency. 16

17 RuleSpeak TM Not Procedural! Example: 99. Check the product number in database SRU [the Sandals R Us database]. If the product number is equal to 422 [the part number of flip-flops] and the product description is equal to plastic flip-flops, then set the new product number in database ASC [The Athens Sandal Company database] equal to 1547 and set the product description equal to Fun-in-the-Sun Flip-Flops else if the product number in database is equal to 423 through 495 [the part numbers of all orthopedic sandals] then set the new product number equal to 1647 and set the product category equal to Good for You, Too Sandals else if Example of Business Rules from a Recent Software Vendor White Paper 17

18 RuleSpeak TM And Not Inscrutable! Example: These items may or may not be available at all times, and sometimes not at all and other times all the time. Menu Item in Restaurant Ft. Bragg, CA Or impossible! Example: Regardless of anything to the contrary in this booklet, if your medical insurance terminates for any reason including death, you may elect within 30 days to continue such medical insurance. From the booklet Group Insurance for I-14 Employees Consolidated Group Trust, The Hartford 18

19 RuleSpeak TM Rules about Rules A rule always contains one of the following rule words must or must not (or should or should not ) only (especially only if ) A rule adds a rule word to terms and facts. A rule always constrains. If not, then it can be expressed as a Permission Statement. Reference: Principles of the Business Rule Approach, Part III. 19

20 About the Business Rules Manifesto Rule- Based Architectures 4.1. A business rules application is intentionally built to accommodate continuous change in business rules. The platform on which it runs should support such continuous change Executing rules directly for example in a rule engine is a better implementation strategy than transcribing them into some procedural form Rules are based on truth values. How a rule s truth value is determined or maintained is hidden from users The relationship between events and rules is generally many-to-many. A rule engine is to business logic as a DBMS is to data. The key question in rule architecture is how rules relate to processes. That s where events come in. Reference: Principles of the Business Rule Approach, Chapter 6. 20

21 Analysis of Rules Based on Change-of-Knowledge State group includes 48.3 status employee X, ME Rule: A group must not include more than one of the following: Union member. Non-union member. nonunion union Symbols: : at time of creation : at time of modification : at time of deletion Event analysis of this rule produces 48.1 When an instance of group is created When an instance of employee is added to an existing group When an instance of employee already included on a group changes status. 21

22 Baseline Criteria for Business Rule Engines What is a Business Rule Architecture? Events must be externalized! Event 1 Event 2 Event 3 Event 4 Event 5 rule 1 rule 2 rule 3 Rule Base rule 4 rule 5 rule 6 Processes, Methods, Procedures, etc. Event Registry Simpler code, more manageable rules and strategic flexibility! 22

23 About the Business Rules Manifesto Violation of Rules 5.1. Rules define the boundary between acceptable and unacceptable business activity Rules often require special or selective handling of detected violations. Such rule violation activity is activity like any other activity To ensure maximum consistency and reusability, the handling of unacceptable business activity should be separable from the handling of acceptable business activity. Now a new system view of doing work Knowledge Companions Reference: Principles of the Business Rule Approach, Chapter 7. 23

24 Basic Business Rule Architecture Processes, Events and Rules... Business Event Place an order Event Create an instance of order Invocation Fire Rule #116 Rule Rule #116 A customer that has placed an order must have an assigned agent. Violation Report error message User Process What error message should be reported back to to the user? 1028csr 24

25 Friendly Processes Normal Business Rules define the boundary between normal and abnormal business activity Rule Violation Activity (RVA) Business Event Place an order Knowledge Event Create an instance of order Invocation Fire Rule #116 Rule Rule #116 A customer that has placed an order must have an assigned agent. Violation Invoke rule violation activity Business Event Assign an agent Process The firing of a rule might detect a violation. This violation can be used as the basis for invoking other pre-scripted activity (aka rule violation activity). This other activity gives the user (if authorized and capable) a chance to correct the violation. Process 1031csr 25

26 What This Means for Adaptability Normal Business Rule Violation Activity (RVA) Business Event Knowledge Event Invocation Rule Violation Business Event Place an order Create an instance of order Fire Rule #116 Rule #116 A customer that has placed an order must have an assigned agent. Invoke rule violation activity Assign an agent Process Process These business processes may be replaced independently 1029csr 26

27 What This Means for Re-Usability Normal Business Rule Violation Activity (RVA) Business Event Knowledge Event Invocation Rule Violation Business Event Place an order Create an instance of order Fire Rule #116 Rule #116 A customer that has placed an order must have an assigned agent. Invoke rule violation activity Assign an agent Process Process Pre-existing existing business process invoked here 1032csr 27

28 The Business Rules Manifesto: Summary Feedback Welcome... Thank You! 28