diff --git a/spec/latest/core/core.jsonld b/spec/latest/core/core.jsonld
index f186896..5a91e3d 100644
--- a/spec/latest/core/core.jsonld
+++ b/spec/latest/core/core.jsonld
@@ -28,6 +28,12 @@
     "method": "hydra:method",
     "expects": { "@id": "hydra:expects", "@type": "@vocab" },
     "returns": { "@id": "hydra:returns", "@type": "@vocab" },
+    "retractedOperation": { "@id": "hydra:retractedOperation", "@type": "@vocab" },
+    "reason": { "@id": "hydra:reason", "@type": "@vocab" },
+    "RetractedOperationSpecification": "hydra:RetractedOperationSpecification",
+    "UnavailabilityReason": "hydra:UnavailabilityReason",
+    "Unavailable": "hydra:Unavailable",
+    "Unauthorized": "hydra:Unauthorized",
     "possibleStatus": { "@id": "hydra:possibleStatus", "@type": "@id" },
     "Status": "hydra:Status",
     "statusCode": "hydra:statusCode",
@@ -167,13 +173,65 @@
       "isDefinedBy": "http://www.w3.org/ns/hydra/core",
       "vs:term_status": "testing"
     },
+    {
+      "@id": "hydra:retractedOperation",
+      "@type": "rdf:Property",
+      "label": "retracted operation",
+      "comment": "Retracts available operations.",
+      "range": "hydra:RetractedOperationSpecification",
+      "domain": "hydra:Resource",
+      "isDefinedBy": "http://www.w3.org/ns/hydra/core",
+      "vs:term_status": "testing"
+    },
+    {
+      "@id": "hydra:RetractedOperationSpecification",
+      "@type": "hydra:Class",
+      "label": "retracted operation specification",
+      "comment": "Describes which and why an operation is retracted.",
+      "isDefinedBy": "http://www.w3.org/ns/hydra/core",
+      "vs:term_status": "testing"
+    },
+    {
+      "@id": "hydra:reason",
+      "@type": "rdf:Property",
+      "label": "reason",
+      "comment": "Reason of why the operation is retracted.",
+      "range": "hydra:UnavailabilityReason",
+      "domain": "hydra:RetractedOperationSpecification",
+      "isDefinedBy": "http://www.w3.org/ns/hydra/core",
+      "vs:term_status": "testing"
+    },
+    {
+      "@id": "hydra:UnavailabilityReason",
+      "@type": "hydra:Class",
+      "label": "Unavailability reason",
+      "comment": "Provides reasons why the operation cannot be invoked.",
+      "isDefinedBy": "http://www.w3.org/ns/hydra/core",
+      "vs:term_status": "testing"
+    },
+    {
+      "@id": "hydra:Unavailable",
+      "@type": "hydra:UnavailabilityReason",
+      "label": "Unavailable",
+      "comment": "States an operation previously announced is unavailable in current circumstances.",
+      "isDefinedBy": "http://www.w3.org/ns/hydra/core",
+      "vs:term_status": "testing"
+    },
+    {
+      "@id": "hydra:Unauthorized",
+      "@type": "hydra:Availability",
+      "label": "Unauthorized",
+      "comment": "States an operation previously announced should not be invoked as the current user is not authorized to invoke it.",
+      "isDefinedBy": "http://www.w3.org/ns/hydra/core",
+      "vs:term_status": "testing"
+    },
     {
       "@id": "hydra:possibleStatus",
       "@type": "hydra:Link",
       "label": "possible status",
       "comment": "A status that might be returned by the Web API (other statuses should be expected and properly handled as well)",
       "range": "hydra:Status",
-      "domainIncludes": ["hydra:ApiDocumentation", "hydra:Operation"],
+      "domainIncludes": ["hydra:ApiDocumentation", "hydra:Operation", "hydra:RetractedOperationSpecification"],
       "isDefinedBy": "http://www.w3.org/ns/hydra/core",
       "vs:term_status": "testing"
     },
@@ -276,7 +334,7 @@
       "@type": "rdf:Property",
       "label": "method",
       "comment": "The HTTP method.",
-      "domain": "hydra:Operation",
+      "domainIncludes": ["hydra:Operation", "hydra:RetractedOperationSpecification"],
       "range": "xsd:string",
       "isDefinedBy": "http://www.w3.org/ns/hydra/core",
       "vs:term_status": "testing"
@@ -286,7 +344,7 @@
       "@type": "hydra:Link",
       "label": "expects",
       "comment": "The information expected by the Web API.",
-      "domain": "hydra:Operation",
+      "domainIncludes": ["hydra:Operation", "hydra:RetractedOperationSpecification"],
       "rangeIncludes": ["rdfs:Resource", "hydra:Resource", "rdfs:Class", "hydra:Class"],
       "isDefinedBy": "http://www.w3.org/ns/hydra/core",
       "vs:term_status": "testing"
@@ -296,7 +354,7 @@
       "@type": "hydra:Link",
       "label": "returns",
       "comment": "The information returned by the Web API on success",
-      "domain": "hydra:Operation",
+      "domainIncludes": ["hydra:Operation", "hydra:RetractedOperationSpecification"],
       "rangeIncludes": ["rdfs:Resource", "hydra:Resource", "rdfs:Class", "hydra:Class"],
       "isDefinedBy": "http://www.w3.org/ns/hydra/core",
       "vs:term_status": "testing"
diff --git a/spec/latest/core/index.html b/spec/latest/core/index.html
index e1a210c..9aff512 100644
--- a/spec/latest/core/index.html
+++ b/spec/latest/core/index.html
@@ -744,6 +744,84 @@ <h3>Documenting a Web API</h3>
       without elevating it to the <i>Link</i> SHOULD NOT be implemented as clients
       may not discover such a construct correctly.</p>
 
+    <p>There are rare situations when some supported operations once announced in the
+      API documentation should be retracted, i.e. to reflect current state of the 
+      application or current user capabilities (or lack of them). It is doable
+      with the <i>retractedOperation<i> predicate that can be added to the reasorce
+	  the same way as the <i>operation</i> is. By default all operations are available
+	  without limits and it is up for the server to change that, and for the client
+	  to discover any discrepancies compared against the API documentation in the runtime.
+	  Yet server may want to inform the client that at the very moment an operation is either 
+      <i>Unavailable</i> or <i>Unauthorized</i> with a <i>reason</i> predicate.
+	  The latter MAY be used to notify client that the user used to invoke
+	  the request that provides operation availability information is currently
+	  not authorized for that very operation to be invoked. The former on the other hand
+	  MAY be used to inform that the operation is currently forbidden and client
+	  SHOULD NOT invoke it. Server MAY also provide more custom reasons for which
+	  the operation is not available but it SHOULD provide at least one of the
+	  <i>Hydra</i> built in reasons.</p>
+
+    <p>The <i>retractedOperation</i> MUST NOT be used in context of the <i>ApiDocumentation</i>.
+	  The <i>retractedOperation</i> predicate also MUST take precedence over both 
+	  <i>operation</i> and <i>supportedOperation</i> declaration and overrides them.
+      The operation that comes with <i>retractedOperation</i> predicate SHOULD be identified
+      using any of the below enlisted methods:
+      <ul>
+        <li>Iri by using <i>object</i> predicate</li>
+        <li>exact match of a resource described by <i>possibleStatus</i>, <i>method</i>,
+          <i>expects</i>, <i>returns</i> or combination of those.</li>
+      </ul>
+    </p>
+
+    <pre class="example nohighlight" data-transform="updateExample"
+         title="Retracting operations - declaration of supported operations">
+      <!--
+      {
+        "@context": "http://www.w3.org/ns/hydra/context.jsonld",
+        "@id": "http://api.example.com/doc/#comments",
+        "@type": "Link",
+        "supportedOperation": [
+          {
+            "@type": "Operation",
+            "method": "POST",
+            "expects": "http://api.example.com/doc/#Upload"
+          },
+          {
+            "@type": "Operation",
+            "method": "POST",
+            "expects": "http://api.example.com/doc/#Comment"
+          }
+        ]
+      }
+      -->
+    </pre>
+    <pre class="example nohighlight" data-transform="updateExample"
+         title="Retracting operations - matching">
+      <!--
+      {
+        "@context": "http://www.w3.org/ns/hydra/context.jsonld",
+        "@id": "http://api.example.com/doc/",
+        "@type": "Collection",
+        "retractedOperation": [
+          {
+            "@type": "Operation",
+            "method": "POST",
+            "expects": "http://api.example.com/doc/#Upload",
+            "reason": "Unavailable"
+          }
+        ]
+      }
+      -->
+    </pre>
+
+    <p>In the example above the operation that expects an uploaded file became
+      <i>Unavailable</i>, while the one expecting a comment remains available as
+      the <i>expects</i> predicate does not match any supported operations.
+      It is still recommended to mark operations being subject for further
+      restrictions with an Iri as from the client perspective this may be
+      easier to implement simple literal Iri comparison rather than to compare
+      graphs of objects.</p>
+
     <p>These are the simple example scenarios and possible usages are not
       limited to those described above.</p>