# The Client Classpath Apache ActiveMQ Artemis requires just a single jar on the *client classpath*. > **Warning** > > The client jar mentioned here can be found in the `lib/client` directory of the > Apache ActiveMQ Artemis distribution. Be sure you only use the jar from the correct > version of the release, you *must not* mix and match versions of jars > from different Apache ActiveMQ Artemis versions. Mixing and matching different jar > versions may cause subtle errors and failures to occur. Whether you are using JMS or just the Core API simply add the `artemis-jms-client-all.jar` from the `lib/client` directory to your client classpath. This is a "shaded" jar that contains all the Artemis code plus dependencies (e.g. JMS spec, Netty, etc.).