diff --git a/NSspi/Contexts/ClientContext.cs b/NSspi/Contexts/ClientContext.cs
index 60374ce..c68799d 100644
--- a/NSspi/Contexts/ClientContext.cs
+++ b/NSspi/Contexts/ClientContext.cs
@@ -24,7 +24,7 @@ namespace NSspi.Contexts
 
         public SecurityStatus Init( byte[] serverToken, out byte[] outToken )
         {
-            long expiry = 0;
+            long rawExpiry = 0;
 
             SecurityStatus status;
 
@@ -82,7 +82,7 @@ namespace NSspi.Contexts
                         ref this.ContextHandle.rawHandle,
                         outAdapter.Handle,
                         ref this.finalAttribs,
-                        ref expiry
+                        ref rawExpiry
                     );
                 }
                 else
@@ -101,7 +101,7 @@ namespace NSspi.Contexts
                             ref this.ContextHandle.rawHandle,
                             outAdapter.Handle,
                             ref this.finalAttribs,
-                            ref expiry
+                            ref rawExpiry
                         );
                     }
                 }
@@ -111,6 +111,8 @@ namespace NSspi.Contexts
             {
                 this.Initialized = true;
                 outToken = null;
+
+                this.Expiry = TimeStamp.Calc( rawExpiry );
             }
             else if ( status == SecurityStatus.ContinueNeeded )
             {
diff --git a/NSspi/Contexts/Context.cs b/NSspi/Contexts/Context.cs
index 37ebbf3..16acc7b 100644
--- a/NSspi/Contexts/Context.cs
+++ b/NSspi/Contexts/Context.cs
@@ -53,6 +53,8 @@ namespace NSspi.Contexts
             }
         }
 
+        public DateTime Expiry { get; protected set; }
+
         public bool Disposed { get; private set; }
 
         public void Dispose()
diff --git a/NSspi/Contexts/ServerContext.cs b/NSspi/Contexts/ServerContext.cs
index 39f66e5..9f80768 100644
--- a/NSspi/Contexts/ServerContext.cs
+++ b/NSspi/Contexts/ServerContext.cs
@@ -30,7 +30,7 @@ namespace NSspi.Contexts
             SecureBuffer outBuffer = new SecureBuffer( new byte[12288], BufferType.Token );
 
             SecurityStatus status;
-            long expiry = 0;
+            long rawExpiry = 0;
 
             SecureBufferAdapter clientAdapter;
             SecureBufferAdapter outAdapter;
@@ -50,7 +50,7 @@ namespace NSspi.Contexts
                             ref this.ContextHandle.rawHandle,
                             outAdapter.Handle,
                             ref this.finalAttribs,
-                            ref expiry
+                            ref rawExpiry
                         );
                     }
                     else
@@ -64,7 +64,7 @@ namespace NSspi.Contexts
                             ref this.ContextHandle.rawHandle,
                             outAdapter.Handle,
                             ref this.finalAttribs,
-                            ref expiry
+                            ref rawExpiry
                         );
 
 
@@ -87,6 +87,8 @@ namespace NSspi.Contexts
                     nextToken = null;
                 }
 
+                this.Expiry = TimeStamp.Calc( rawExpiry );
+
                 InitProviderCapabilities();
             }
             else if ( status == SecurityStatus.ContinueNeeded )
diff --git a/NSspi/Credentials/Credential.cs b/NSspi/Credentials/Credential.cs
index 95371e4..55a8df0 100644
--- a/NSspi/Credentials/Credential.cs
+++ b/NSspi/Credentials/Credential.cs
@@ -19,14 +19,15 @@ namespace NSspi.Credentials
         private SecurityPackage securityPackage;
 
         private SafeCredentialHandle safeCredHandle;
-        private long expiry;
+
+        private DateTime expiry;
 
         public Credential(SecurityPackage package, CredentialType credentialType)
         {
             this.disposed = false;
             this.securityPackage = package;
 
-            this.expiry = 0;
+            this.expiry = DateTime.MinValue;
 
             Init( package, credentialType );
         }
@@ -35,6 +36,7 @@ namespace NSspi.Credentials
         {
             string packageName;
             CredentialUse use;
+            long rawExpiry = 0;
 
             // -- Package --
             if ( package == SecurityPackage.Kerberos )
@@ -90,7 +92,7 @@ namespace NSspi.Credentials
                    IntPtr.Zero,
                    IntPtr.Zero,
                    ref this.safeCredHandle.rawHandle,
-                   ref this.expiry
+                   ref rawExpiry
                );
             }
 
@@ -98,6 +100,8 @@ namespace NSspi.Credentials
             {
                 throw new SSPIException( "Failed to call AcquireCredentialHandle", status );
             }
+
+            this.expiry = TimeStamp.Calc( rawExpiry );
         }
 
         ~Credential()
@@ -177,6 +181,14 @@ namespace NSspi.Credentials
             }
         }
 
+        public DateTime Expiry
+        {
+            get
+            {
+                return this.expiry;
+            }
+        }
+
         public SafeCredentialHandle Handle
         {
             get
@@ -203,6 +215,5 @@ namespace NSspi.Credentials
                 this.disposed = true;
             }
         }
-
     }
 }
diff --git a/NSspi/NSspi.csproj b/NSspi/NSspi.csproj
index b8c65d8..dba79ff 100644
--- a/NSspi/NSspi.csproj
+++ b/NSspi/NSspi.csproj
@@ -80,6 +80,7 @@
     <Compile Include="SecurityStatus.cs" />
     <Compile Include="SSPIException.cs" />
     <Compile Include="SspiHandle.cs" />
+    <Compile Include="TimeStamp.cs" />
   </ItemGroup>
   <ItemGroup />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
diff --git a/NSspi/TimeStamp.cs b/NSspi/TimeStamp.cs
new file mode 100644
index 0000000..32ece40
--- /dev/null
+++ b/NSspi/TimeStamp.cs
@@ -0,0 +1,18 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace NSspi
+{
+    public static class TimeStamp
+    {
+        public static readonly DateTime Epoch = new DateTime( 1601, 1, 1, 0, 0, 0, DateTimeKind.Utc );
+
+        public static DateTime Calc( long rawExpiry )
+        {
+            return TimeStamp.Epoch.AddTicks( rawExpiry );
+        }
+    }
+}