# Using Client State Management

When client state management is enabled for an application, you can use the system to keep track of any number of variables associated with a particular client.

## Creating a client variable

To create a client variable and set the value of the parameter, use the CFSET or CFPARAM tag., for example:

    <CFSET Client.FavoriteColor="Red">

Once a client variable has been set in this manner, it is available for use within any application page in your application that is accessed by the client for whom the variable is set.

The following example shows how to use the CFPARAM tag to check for the existence of a client parameter and to set a default value if the parameter does not already exist:

    <CFPARAM NAME="Client.FavoriteColor" DEFAULT="Red">