Project reference conditional include with multiple conditions

Here's a snippet from my csproj file:

<ProjectReference Include="..\program_data\program_data.csproj" Condition="'$(Configuration)'=='Debug'">
      <Project>{4F9034E0-B8E3-448E-8794-CF9B9A5E7D46}</Project>
      <Name>program_data</Name>
</ProjectReference>

What I'd like to do is include program_data.dll for multiple build configurations, for example, both Release and Debug.

I tried doing the following

Condition="'$(Configuration)'=='Debug' || '$(Configuration)'=='Release'"

but Visual Studio chokes on this.

Is there a way I can do this, or must I have a separate <ProjectReference> for each build config?

You should use Or, not ||:

Condition="'$(Configuration)'=='Debug' Or '$(Configuration)'=='Release'"