What is a requirement, what interpretations are there and how should requirements be expressed?
The description of the desired range of functions
There are many different definitions for the term requirement. The Association for Work Design, Company Organisation and Enterprise Development (REFA) defines it as “the totality of physical and mental requirements for performing work”. In psychology, requirements refer to the needs of people to perform specific tasks. And in recruitment, they are summarised for potential employees and declared as qualification profiles.
What is a requirement in software development or product development? The International Requirements Engineering Board (IREB) defines a requirement as
- a need that is perceived by a stakeholder.
- an ability or characteristic that a system should have.
- a documented representation of a need, skill or property.
For the International Institute of Business Analysis (IIBA), a requirement is a useful representation of a need that is usually described by documents. The Business Analysis Body of Knowledge Guide (BABOK) has four categories of requirements:
- Business requirements are goals and results that describe the reason for initiating changes.
- Stakeholder requirements describe the needs of the stakeholders that must be fulfilled in order to meet the business requirements.
- Solution Requirements define the performance and quality of a solution that meets stakeholder requirements. They can be subdivided into functional and non-functional requirements.
- Transistion Requirements describe the performance of a solution to facilitate the transition from the actual to the target state.
In many organisations there is also a division into functional and non-functional or quality requirements, as well as legal, moral/ethical, organisational and technological parameters. Due to the variance of the term and the different interpretations, organisations should urgently pay attention to a common understanding of all participants.
Objectives when collecting requirements
The use of defined processes to work with requirements is also recommended. The aim should be, among other things, to identify
- assessed according to importance and/or stability,
- and traceable
Principles for working with requirements
In 2020, the International Requirements Engineering Board (IREB) defined nine principles for working with requirements. These principles apply to all tasks, activities or practices in dealing with requirements¹:
- Value-orientation: Requirements are a means to an end, not an end in itself.
- Stakeholders: Requriements engineering is about satisfying the stakeholders’ desires and needs.
- Shared understanding: Successful systems development is impossible without a common basis.
- Context: Systems cannot be understood in isolation.
- Problem – Requirement – Solution: An inevitably intertwined triple.
- Validation: Non-validated requirements are useless.
- Evolution: Changing requirements are no accident, but the normal case.
- Innovation: More of the same is not enough.
- Systematic and disciplined work: We can’t do without in requirements engineering.
Questions in the context of requirements
There are a number of questions when dealing with desired scopes of functions. You can find answers to some of the questions in our blog:
- What are the best practices in preparing, conducting and following up on requirements workshops? Which questions help and how do you deal with conflicts?
- Products and systems are often misused. What are the reasons for this and why are such misuse cases suitable for requirements elicitation?
- How can you reduce the scope of functions if the set of desired features is too large? Which criteria are suitable for this?
- Requirements analysis knows numerous methods and techniques. Which of these methods work remotely or online? And what additional tips are there?
- When exchanging requirements, there are technical and procedural challenges. How can we achieve a loss-free exchange?
We are sure you can think of more questions. Please contact us and we will try to answer your questions or publish corresponding articles.
The attributes that are often used to record requirements can be found here »
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