Within systems engineering, quality attributes are realized non-functional requirements used to evaluate the performance of a system. These are sometimes named architecture characteristics, or "ilities" after the suffix many of the words share. They are usually architecturally significant requirements that require architects' attention.^[1]

In software architecture, these attributed are known as "architectural characteristic" or non-functional requirements. Note that it's software architects' responsibility to match these attributes with business requirements and user requirements ^[2]

Quality attributes

Notable quality attributes include:

Many of these quality attributes can also be applied to data quality.

Common subsets

• Together, reliability, availability, serviceability, usability and installability, are referred to as RASUI.
• Functionality, usability, reliability, performance and supportability are together referred to as FURPS in relation to software requirements.
• Agility in working software is an aggregation of seven architecturally sensitive attributes: debuggability, extensibility, portability, scalability, securability, testability and understandability.
• For databases reliability, availability, scalability and recoverability (RASR), is an important concept.
• Atomicity, consistency, isolation (sometimes integrity), durability (ACID) is a transaction metric.
• When dealing with safety-critical systems, the acronym reliability, availability, maintainability and safety (RAMS) is frequently used.^{[citation needed]}
• Dependability is an aggregate of availability, reliability, safety, integrity and maintainability.
  • Integrity depends on security and survivability.
  • Security is a composite of confidentiality, integrity and availability. Security and dependability are often treated together.