Data without context is meaningless; data without trust is useless. "2017-12-18" is nothing but a string—until it becomes a birthdate, a wedding, or the moment a security camera registered you. Handling such highly personal data requires trust. When your personal data is shared with someone, you must be able to trust that they will only use it in the way you agreed to. When someone receives your data, they must be able to trust that it is correct and that they are allowed to use it for the intended purpose. Auditors need to be able to challenge and verify this trust relationship, for example under GDPR. Unfortunately, trust is not baked into our data interfaces today: they only provide access to the raw data, disregarding the context that is crucial to its correct treatment. We need to standardize interfaces that carry data in a trust envelope, which encapsulates usage policies and provenance to ensure that data can flow in more responsible ways.