# Expressions in the EHR

This part of the guide describes one way in which postcoordination might be applied in an EHR. This involves introducing the steps involved with setting up an expression repository, including approaches taken to create and add expressions to the repository.

This section also introduces how postcoordination can be implemented to support essential EHR tasks including entering, storing, displaying, querying, and communicating expressions. In addition, references to the terminology services required to support these approaches will be provided to function as a practical source of reference for implementers wishing to enable postcoordination in their EHR.

<figure><img src="/files/s74rxiOfK5k1luPTGBdR" alt=""><figcaption><p>Components and services required to enable postcoordination in an EHR</p></figcaption></figure>

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