The types of non-functional requirements listed below are rather common for ICT systems, and substantial literature and examples exist for each of them.

These are some recommendations for handling non functional requirements during requirements gathering:

  1. A mature ICT department may have a standard (requirements document) template listing for important NFR types the common options in the organisation (options that are backed by capabilities, or for which there are known solutions). If such a template is provided, and for the NFRs included in it, the stakeholders simply have to select which option fits their need. If none does, this must be communicated early to the ICT department.
  2. Often, non functional requirements will be raised alongside specific functional requirements, work that must be performed, or data. In such a case it is an option to list the requirement in the suitable slot as part of the Stakeholder template, Business use case (BUC) template, Business object template, or another template. On the other hand, when the NFR matters for several functions or a domain, then it may be better to list it in a separate chapter "Non Functional Requirements", as illustrated by #lib11 - Non-functional requirements (NFR) of #2030library.

NFR type Name Definition Examples
10 Look&Feel Requirements
10a Look&Feel - Appearance See Volère
10b Look&Feel - Style See Volère
11 Usability&Humanity Requirements
11a Ease of Use See Volère
11b Personalization&Internationalization See Volère
11c Learning See Volère
11d Understandability&Politeness See Volère
11e Accessibility See Volère
12 Performance Requirements
12a Speed&Latency See Volère
12b Safety-Critical See Volère
12c Precision or Accuracy See Volère
12d Reliability&Availability See Volère
12e Robustness or Fault-Tolerance See Volère
12f Capacity See Volère
12g Scalability or Extensibility See Volère
12h Longevity See Volère
13 Operational and Environmental Requirements
13a Expected Physical Environment See Volère
13b Interfacing with Adjacent Systems See Volère
13c Productization See Volère
13d Release See Volère
14 Maintainability and Support Requirements
14a Maintenance See Volère
14b Supportability See Volère
14c Adaptability See Volère
15 Security Requirements
15a Access See Volère
15b Integrity See Volère
15c Privacy See Volère
15d Audit See Volère
15e Immunity See Volère
16 Cultural&Political Requirements
16a Cultural See Volère
16b Political See Volère
17 Legal Requirements
17a Compliance See Volère
17b Standards See Volère

Acknowledgement: Volère Template chapter numbers and names used to tag the types of non-functional requirements.