Business Requirements Categories

Business requirements are typically classified into three business requirements categories.  The categories are functional requirements, non-functional requirements and design constraints.  The definition of these categories are:

Functional Requirements:
Describe the system features or things the system must do to support the end user’s business responsibilities. i.e. The system shall allow the ATM User to deposit funds into their individual bank account.

Non-Functional Requirements:
Describe properties the system must have (e.g. performance, availability, accessibility). What are the qualities the system needs to have for the user? i.e. The system shall provide an ATM transaction response time of 5 seconds.
There are four categories of non-functional requirements:

  • Usability – ease with which a user can learn to operate and usability design standards
  • Reliability – availability of the system, nightly backup, logs, nightly backup
  • Performance – maximum users, response time
  • Supportability – Error messages, error logs

Design Constraints:
Limits the development in some way. Such as, defining an operating system the system must run on, or defining which programming language must be used to implement the system. i.e. The ATM must have touch pad screens.

To learn more about how to elicit and write effective business requirements register for Pierson’s Virtual Business Requirements Gathering & Writing Class.

By Joy MatthewsJoy Matthews on Google+

Joy Matthews is the cofounder and Vice President of Methodology Development and Training for Pierson Requirements Group, Inc. which was launched in 1990. She is an experienced Methodologist and Facilitator with expertise in UML, Data Techniques and the JAD/RAD process. She has trained over 1,500 consultants and more than 5,000 corporate IT professionals in the latest UML using the JAD/RAD process and facilitation techniques. Joy is an expert in best practices and industry standards and has helped numerous companies qualify to CMM level 3. She has been instrumental in improving the requirements management, design and testing processes at many large corporations. She has facilitated and managed projects for all phases of the system development life cycle. Joy is the co-author of Pierson’s repeatable development methodology and author of the Requirements Gathering and Facilitation classes and Testing classes. Joy has also developed a class for how to facilitate for Business Process Management.