How to include a config file for .Net

Is there a way to have the main .net configuration file app.config/web.config include another configuration file? I have a need to keep things in separate files, but link them together.

Here is a sample of what I want to include:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
      <section name="LocationSearch.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
    </sectionGroup>
  </configSections>
  <applicationSettings>
    <LocationSearch.Properties.Settings>
        <setting name="MapQuestApiKey" serializeAs="String">
        <value>some value here...</value>
        </setting>
        <setting name="MapQuestClientCode" serializeAs="String">
        <value>another value here...</value>
        </setting>
    </LocationSearch.Properties.Settings>
  </applicationSettings>
</configuration>