The System.Security.Principal namespace defines a principal object that represents the security context under which code is running. For more information, see Role-Based Security.

 Classes

	Class	Description
	GenericIdentity	Represents a generic user.
	GenericPrincipal	Represents a generic principal.
	IdentityNotMappedException	Represents an exception for a principal whose identity could not be mapped to a known identity.
	IdentityReference	Represents an identity and is the base class for the NTAccount and SecurityIdentifier classes. This class does not provide a public constructor, and therefore cannot be inherited.
	IdentityReferenceCollection	Represents a collection of IdentityReference objects and provides a means of converting sets of IdentityReference-derived objects to IdentityReference-derived types.
	NTAccount	Represents a user or group account.
	SecurityIdentifier	Represents a security identifier (SID) and provides marshaling and comparison operations for SIDs.
	WindowsIdentity	Represents a Windows user.
	WindowsImpersonationContext	Represents the Windows user prior to an impersonation operation.
	WindowsPrincipal	Allows code to check the Windows group membership of a Windows user.

 Interfaces

	Interface	Description
	IIdentity	Defines the basic functionality of an identity object.
	IPrincipal	Defines the basic functionality of a principal object.

 Enumerations

	Enumeration	Description
	PrincipalPolicy	Specifies how principal and identity objects should be created for an application domain. The default is UnauthenticatedPrincipal.
	TokenAccessLevels	Defines the privileges of the user account associated with the access token.
	TokenImpersonationLevel	Defines security impersonation levels. Security impersonation levels govern the degree to which a server process can act on behalf of a client process.
	WellKnownSidType	Defines a set of commonly used security identifiers (SIDs).
	WindowsAccountType	Specifies the type of Windows account used.
	WindowsBuiltInRole	Specifies common roles to be used with IsInRole.