The design of Human Services Data Specification (HSDS) is based on five principles: simplicity, factuality, fidelity, provenance, and accessibility.
The underlying model is simple, consisting of four entities and associated properties that support who, what, where, when, and how questions. The relationships between the entities are flexible and can model the majority of use cases for human services data. The goal is to build the simplest useful thing.
The data provided in HSDS are factual. This means that the information is verifiable and can be reproduced across different systems and applications.
Data fidelity is important. Data reproduced and used across different information systems must retain the same meaning and be represented in a consistent way. Toward this end, HSDS leverages the use of existing standards such as ISO time and date formats.
The format also specifies information about the provenance of the data, as well as a history of changes, in order to provide an authoritative source. The format supports column level metadata for a high degree of granularity.
In order to ensure accessibility, the data must be a machine-readable and -writable format that can also be created, updated and deleted with a basic text editor.