Companies and public institutions invest valuable resources in a secure IT infrastructure to ensure data security. Yet security measures such as encryption, access controls, and audit logs do not prevent sticky notes with passwords from being taped to computer screens.
This scenario is not merely a cliché. It is a real-world problem and a symptom of the fact that even the best technical solutions can be circumvented if they are not user-friendly. This is precisely where the concept of “Usable Privacy” comes into play. Our team at Fraunhofer AISEC is conducting systematic research into the connections between user-friendliness and data protection and developing methods to combine the two.
Those who view privacy solely from a technical perspective lose sight of the human factor. To create a usable privacy solution, it is essential to focus on both the users whose data is being processed and those who process it.
1. What Do “Privacy” and “Usability” Mean?
1.1 Privacy: Informational Self-Determination
In the context of IT security, privacy primarily refers to the protection of personal data and the right to informational self-determination. It is about controlling who uses which personal data and for what purpose. In the EU, this right is codified by the GDPR. Article 12 of the GDPR requires that information regarding data processing be accurate, transparent, understandable, and easily accessible.
1.2 Usability: Effectiveness, Efficiency, and Satisfaction
ISO 9241-11 defines usability as the extent to which a system, product or service can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use. Jakob Nielsen, on the other hand, defines usability using five quality components: learnability, efficiency, memorability, error rate, and satisfaction. Essentially, high usability aims to ensure that users can achieve their goals easily and quickly, with as few errors as possible, while remaining satisfied with the product.
2. Why Poor Usability is a Security Risk
Poor usability leads users to bypass security measures. This creates new and often significant risks. Complicated policies and frequent password changes are impractical to implement, so users are tempted to write down their passwords and store them insecurely.
Poor usability can also be intentionally exploited to obtain consent for data collection. Manipulative or deceptive design tricks take advantage of the lack of usability of cookie consent dialogs, for example: The button to consent to cookies is large and green, while the button to opt out is small and gray. Users are thus pushed toward privacy-unfriendly settings through targeted interface design.
3. Methods for Implementing Usable Privacy
There are a variety of techniques, tools, and methods for implementing Usable Privacy. The following section provides a brief introduction to some of the most common ones. We distinguish between three levels: Design, Evaluations by Experts and User Testing.
3.1 Tools for Design and Development Teams
Involving usability experts is necessary to ensure good usability. However, some of the tools that these experts use can also support design and development teams in their work. Personas are fictional but realistic descriptions of typical users of the product. Usability experts use them to make target audiences more tangible. During the design and development process, personas can help prioritize features or make design decisions that benefit the target audience.
For optimal usable privacy, personas should also reflect different security needs and approaches to handling personal data.
User journeys and user flows describe, from the users’ perspective, their path to achieving their desired goal. This can be done at varying levels of detail. User journeys are broad, high-level representations of the user’s “journey” and span days, weeks, or months. User flows, on the other hand, are granular and describe individual steps of the user journey within minutes. Both help to understand interactions relevant to data protection.
Prototypes are simplified representations of a product or product component, ranging from rough sketches to interactive mock-ups. Design ideas should be translated into prototypes as early as possible, because corrections to the finished system are significantly more expensive than adjustments made during the design or development phase. Prototypes can also be used to present design ideas more effectively to team members and stakeholders and allow these ideas to be tested with the target audience.
Design principles and guidelines, such as Don Norman’s design principles or Shneiderman’s “Eight Golden Rules of Interface Design,” provide a solid foundation for user-friendly design. Depending on the purpose of the digital product and its level of maturity, different principles, standards, and guidelines may be applied.
3.2 Evaluations by Usability Experts
Once a prototype exists, it should be evaluated by usability experts. This is because, especially in the early phases of the design and development process, experts can quickly and cost-effectively provide important insights into usable privacy. There are numerous methods for expert evaluations. Two of the better-known options are presented below:
In a heuristic evaluation, usability experts assess a design based on established sets of rules. The best-known are the ten usability heuristics by Molich and Nielsen. Any problems identified are categorized and prioritized according to their severity. It is recommended to involve three to five evaluators to ensure a comprehensive analysis.
In a cognitive walkthrough, experts assume the role of the user and go through all the steps of the user flow. For each step, four questions are answered: Will users attempt to achieve the desired effect? Will they recognize that the correct action could be taken? Will they realize that their action is the right one to achieve their goal? Will they perceive progress after performing the correct action? Additionally, it is noted if users might deviate from the intended procedure.
3.3 User Testing
Expert evaluations cannot replace user testing, user testing reveals the actual difficulties users face, rather than relying on theoretical assumptions. Even just three to five users can provide valuable insights. It is recommended to test iteratively with smaller groups of users and resolve the identified problems between iterations.
Some proven methods include:
- Semi-structured interviews to gain deep insights into the target group’s requirements, preferences, experiences, and attitudes, which are explored using a fixed set of questions and flexible follow-ups.
- Focus groups for group interactions and to identify different perspectives
- Surveys reach a large group of people quickly and inexpensively and can be used at various stages of the design and development process.
- In the thinking-aloud method, users verbalize their thoughts while interacting with a system or prototype.
- A/B tests are used to directly compare design variants. Ideally, the variants differ in only a single design element to ensure that any differences in the results can be attributed to that one change.
4. Concrete Ideas for Better Usable Privacy
Below, we present ideas that have emerged from various projects and discussions in the context of Usable Privacy and that would need to be adapted to the specific use case before implementation.
- Structuring privacy settings according to user needs: Instead of being grouped by hardware type (e.g. camera, microphone), privacy settings could be grouped by desired functions (such as take photos or scan QR codes). This would better align with users’ thought processes.
- Personalized privacy profiles: Predefined but customizable profiles for personalizing privacy settings could help users get started quickly with a service while ensuring a balance between privacy protection and the service’s usability.
- Privacy wizards: Similar to Germany’s “Wahl-O-Mat,” a digital assistant could guide users through privacy decisions. The consequences of individual decisions would need to be clearly presented. In combination with machine learning, certain settings could even be predicted.
- Interactive visualization of data flow: A visual representation of the product and the data flow would give users a better understanding of how their data is processed. By interacting with the respective components, users could modify the data flow.
- LLM-based privacy policy analysis: An AI-powered tool could help users understand lengthy privacy policies by tailoring them to their language proficiency and providing answers to specific questions.
Usage history with integrated data subject rights: Providing a usage history of the data could improve transparency and enable users to track the processing of their data. Many of the rights required by the GDPR, such as the rights of access, erasure, or rectification, could be accessed directly from the usage history. Standardized and automatically generated forms for requests to the relevant data protection authority could make it easier for users to exercise their rights.
5. Conclusion: Usable Privacy is not an Option, but a Necessity
User-friendliness is a crucial factor in data protection. If data protection measures are not user-friendly, users may circumvent or avoid them, creating new risks.
“Usable Privacy” means designing data protection in a way that allows people to actually put it into practice. This requires collaboration between usability experts, data protection specialists and developers from different disciplines.
This article presents various methods for improving usable privacy that can be applied to different phases of the design and development process. While some methods can be implemented by design and development teams, involving usability experts is crucial for applying these methods effectively and ensuring good Usable Privacy.
Would you like to implement usable privacy in your company or product? Feel free to contact us!
This article is based on the scholarly article “Usable Privacy” by Nikolai Lenski, Nadine Warnstädt, Benedikt Schmitz, and Sandra Kostic, published in DuD – Data Protection and Data Security 2/2026, Fraunhofer Institute for Applied and Integrated Security AISEC.
Author
NIKOLAI LENSKI
SHORT BIO NIKOLAI LENSKI »
Nikolai Lenski is a computer scientist specialising in usability, user experience (UX) and human-computer interaction. Since 2020, he has worked at Fraunhofer AISEC, focusing on usable security and privacy. Through user-centred design, he addresses security vulnerabilities and privacy risks in his research.
Contakt:
nikolai.lenski@aisec.fraunhofer.de
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