> For the complete documentation index, see [llms.txt](https://www.mica.wtf/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.mica.wtf/mica.wtf/gdpr/chapter-iv-controller-and-processor-art.-24-43/25.md). # Art. 25 — Data protection by design and by default 1. Taking into account the state of the art, the cost of implementation and the nature, scope, context and purposes of [processing](https://headlesslaw.com/definitions/gdpr/processing/) as well as the risks of varying likelihood and severity for rights and freedoms of natural persons posed by the processing, the [controller](https://headlesslaw.com/definitions/gdpr/controller/) shall, both at the time of the determination of the means for processing and at the time of the processing itself, implement appropriate technical and organisational measures, such as [pseudonymisation](https://headlesslaw.com/definitions/gdpr/pseudonymisation/), which are designed to implement data-protection principles, such as data minimisation, in an effective manner and to integrate the necessary safeguards into the processing in order to meet the requirements of this Regulation and protect the rights of data subjects. 2. The controller shall implement appropriate technical and organisational measures for ensuring that, by default, only [personal data](https://headlesslaw.com/definitions/gdpr/personal-data/) which are necessary for each specific purpose of the processing are processed. That obligation applies to the amount of personal data collected, the extent of their processing, the period of their storage and their accessibility. In particular, such measures shall ensure that by default personal data are not made accessible without the individual's intervention to an indefinite number of natural persons. 3. An approved certification mechanism pursuant to [Article 42](/mica.wtf/gdpr/chapter-iv-controller-and-processor-art.-24-43/42.md) may be used as an element to demonstrate compliance with the requirements set out in paragraphs 1 and 2 of this Article. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://www.mica.wtf/mica.wtf/gdpr/chapter-iv-controller-and-processor-art.-24-43/25.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.