# Working with CQL

The Firely CQL SDK enables you to execute Clinical Quality Language (CQL) logic against FHIR data in .NET applications.
CQL is a standard for expressing clinical rules and logic in a structured, shareable way. It is commonly used for scenarios such as clinical decision support, quality measure evaluation, and rule-based processing of healthcare data.
CQL support in Firely is provided through a separate open-source SDK that integrates with the Firely .NET SDK.

More information can be found in the [GitHub repository for the CQL Engine](https://github.com/FirelyTeam/firely-cql-sdk#getting-started).