I am using TestCategoryAttribute to filter which tests to run during builds and wandered, how to -how to assign multiple test categories.
According to constructor documentation only single category can be specified. However TestCategories Property (plural!)can return multiple categories.
The recommended approach from MSDN How to: Group and Run Automated Tests Using Test Categories is to specify multiple TestCategory attributes like the following
shows how enums can be used instead of strings.
It also explains, that TestCategories Property can be used in derived custom attributes.