This attribute indicates that a program element is compliant with the CLS. If you use non-CLS-compliant classes (such as UInt32 ) in a class marked as compliant, the compiler generates a compliance warning. By default, types without this attribute are not CLS-compliant unless they are contained in a CLS-compliant type or assembly. You can specifically mark non-CLS-compliant members inside a CLS-compliant type using [CLSCompliant(false)] . public sealed class CLSCompliantAttribute : Attribute { // Public Constructors public CLSCompliantAttribute (bool isCompliant ); // Public Instance Properties public bool IsCompliant {get; } } HierarchyObject Attribute CLSCompliantAttribute Valid OnAll |