diff --git a/Medianno/MAAnno.h b/Medianno/MAAnno.h
index 499809f..e7a8f13 100644
--- a/Medianno/MAAnno.h
+++ b/Medianno/MAAnno.h
@@ -22,6 +22,14 @@
 - (NSString *)shortLocation;
 + (NSSet *)keyPathsForValuesAffectingShortLocation;
 
+/*
+ * Tags are never manipulated through the tag objects, but always through
+ * tag description objects.
+ */
+- (NSArray *)tagDescriptions;
+- (void)setTagDescriptions:(NSArray *)tagDescriptions;
++ (NSSet *)keyPathsForValuesAffectingTagDescriptions;
+
 @end
 
 @interface MAAnno (CoreDataGeneratedAccessors)
diff --git a/Medianno/MAAnno.mm b/Medianno/MAAnno.mm
index 41bffbc..25a6ebb 100644
--- a/Medianno/MAAnno.mm
+++ b/Medianno/MAAnno.mm
@@ -8,7 +8,9 @@
 
 #import "MAAnno.h"
 #import "MATag.h"
+#import "MATagDescription.h"
 
+#import <vector>
 
 @implementation MAAnno
 @dynamic location;
@@ -49,4 +51,35 @@
     return [NSSet setWithObject:@"location"];
 }
 
+- (NSArray *)tagDescriptions
+{
+    NSSet *                         tags   = self.tags;
+    std::vector<NSManagedObject *> descs([tags count]);
+    for (MATag * tag in tags) 
+        descs[[tag seqNo]] = [tag tag];
+    
+    return [NSArray arrayWithObjects:&descs[0] count:descs.size()];
+}
+
+- (void)setTagDescriptions:(NSArray *)tagDescriptions
+{
+    NSManagedObjectContext *moc = [self managedObjectContext];
+     
+    int seqNo = 0;
+    std::vector<MATag *>  tags;
+    for (MATagDescription * tagDesc in tagDescriptions) {
+        MATag * tag     = [NSEntityDescription insertNewObjectForEntityForName:@"MATag" inManagedObjectContext:moc];
+        tag.seqNo       = seqNo++;
+        tag.tag         = tagDesc;
+        tag.annotation  = self;
+        tags.push_back(tag);
+    }
+    [self setTags:[NSSet setWithObjects:&tags[0] count:tags.size()]];
+}
+
++ (NSSet *)keyPathsForValuesAffectingTagDescriptions
+{
+    return [NSSet setWithObject:@"tags"];
+}
+
 @end
diff --git a/Medianno/MADocument.xcdatamodeld/MADocument.xcdatamodel/contents b/Medianno/MADocument.xcdatamodeld/MADocument.xcdatamodel/contents
index 44e4d8d..b105729 100644
--- a/Medianno/MADocument.xcdatamodeld/MADocument.xcdatamodel/contents
+++ b/Medianno/MADocument.xcdatamodeld/MADocument.xcdatamodel/contents
@@ -4,7 +4,7 @@
         <attribute name="location" attributeType="String"/>
         <attribute name="notes" attributeType="String"/>
         <relationship name="media" minCount="1" maxCount="1" deletionRule="Nullify" destinationEntity="MAMedia" inverseName="annotations" inverseEntity="MAMedia"/>
-        <relationship name="tags" optional="YES" toMany="YES" deletionRule="Nullify" destinationEntity="MATag" inverseName="annotation" inverseEntity="MATag"/>
+        <relationship name="tags" optional="YES" toMany="YES" deletionRule="Cascade" destinationEntity="MATag" inverseName="annotation" inverseEntity="MATag"/>
     </entity>
     <entity name="MAFolder" representedClassName="MAFolder">
         <attribute name="name" attributeType="String"/>
@@ -17,23 +17,24 @@
         <attribute name="media" attributeType="String"/>
         <attribute name="name" attributeType="String"/>
         <attribute name="notes" attributeType="String"/>
-        <relationship name="annotations" optional="YES" toMany="YES" deletionRule="Nullify" destinationEntity="MAAnno" inverseName="media" inverseEntity="MAAnno"/>
+        <relationship name="annotations" optional="YES" toMany="YES" deletionRule="Cascade" destinationEntity="MAAnno" inverseName="media" inverseEntity="MAAnno"/>
         <relationship name="folder" minCount="1" maxCount="1" deletionRule="Nullify" destinationEntity="MAFolder" inverseName="contents" inverseEntity="MAFolder"/>
     </entity>
     <entity name="MATag" representedClassName="MATag">
+        <attribute name="seqNo" attributeType="Integer 16" defaultValueString="0"/>
         <relationship name="annotation" minCount="1" maxCount="1" deletionRule="Nullify" destinationEntity="MAAnno" inverseName="tags" inverseEntity="MAAnno"/>
         <relationship name="tag" minCount="1" maxCount="1" deletionRule="Nullify" destinationEntity="MATagDescription" inverseName="uses" inverseEntity="MATagDescription"/>
     </entity>
     <entity name="MATagDescription" representedClassName="MATagDescription">
         <attribute name="name" attributeType="String"/>
-        <attribute name="notes" optional="YES" attributeType="String"/>
-        <relationship name="uses" optional="YES" toMany="YES" deletionRule="Nullify" destinationEntity="MATag" inverseName="tag" inverseEntity="MATag"/>
+        <attribute name="notes" attributeType="String"/>
+        <relationship name="uses" optional="YES" toMany="YES" deletionRule="Cascade" destinationEntity="MATag" inverseName="tag" inverseEntity="MATag"/>
     </entity>
     <elements>
-        <element name="MAMedia" positionX="-1116" positionY="-882" width="128" height="135"/>
-        <element name="MATagDescription" positionX="-866" positionY="-576" width="128" height="90"/>
         <element name="MAAnno" positionX="-1296" positionY="-585" width="128" height="105"/>
         <element name="MAFolder" positionX="-864" positionY="-873" width="180" height="105"/>
-        <element name="MATag" positionX="-1044" positionY="-684" width="128" height="75"/>
+        <element name="MAMedia" positionX="-1116" positionY="-882" width="128" height="135"/>
+        <element name="MATag" positionX="-1044" positionY="-678" width="126" height="75"/>
+        <element name="MATagDescription" positionX="-866" positionY="-576" width="128" height="90"/>
     </elements>
 </model>
\ No newline at end of file
diff --git a/Medianno/MATag.h b/Medianno/MATag.h
index 9fa7c68..bc36661 100644
--- a/Medianno/MATag.h
+++ b/Medianno/MATag.h
@@ -13,6 +13,7 @@
 @interface MATag : NSManagedObject {
 @private
 }
+@property (nonatomic) int seqNo;
 @property (nonatomic, retain) NSManagedObject *tag;
 @property (nonatomic, retain) NSManagedObject *annotation;
 
diff --git a/Medianno/MATag.mm b/Medianno/MATag.mm
index 4647347..6ae9e6f 100644
--- a/Medianno/MATag.mm
+++ b/Medianno/MATag.mm
@@ -10,6 +10,7 @@
 
 
 @implementation MATag
+@dynamic seqNo;
 @dynamic tag;
 @dynamic annotation;