diff --git a/README.md b/README.md
index 097d567911..2ae7203922 100644
--- a/README.md
+++ b/README.md
@@ -138,7 +138,7 @@ Container fields are used for meta information about the specific container that
 
 ## <a name="destination"></a> Destination fields
 
-Destination fields describe details about the destination of a packet/event.
+Destination fields describe details about the destination of a packet/event. Destination fields are usually populated in conjuction with source fields.
 
 
 | Field  | Description  | Level  | Type  | Example  |
@@ -404,7 +404,7 @@ The service fields describe the service for or from which the data was collected
 
 ## <a name="source"></a> Source fields
 
-Source fields describe details about the source of a packet/event.
+Source fields describe details about the source of a packet/event. Source fields are usually populated in conjuction with destination fields.
 
 
 | Field  | Description  | Level  | Type  | Example  |
diff --git a/fields.yml b/fields.yml
index 87704127c9..c05777b20b 100644
--- a/fields.yml
+++ b/fields.yml
@@ -239,7 +239,7 @@
       group: 2
       description: >
         Destination fields describe details about the destination of a
-        packet/event.
+        packet/event. Destination fields are usually populated in conjuction with source fields.
       type: group
       fields:
     
@@ -1222,7 +1222,7 @@
       group: 2
       description: >
         Source fields describe details about the source of a
-        packet/event.
+        packet/event. Source fields are usually populated in conjuction with destination fields.
       type: group
       fields:
     
diff --git a/schemas/destination.yml b/schemas/destination.yml
index e9f5ed2049..fea490e17f 100644
--- a/schemas/destination.yml
+++ b/schemas/destination.yml
@@ -4,7 +4,7 @@
   group: 2
   description: >
     Destination fields describe details about the destination of a
-    packet/event.
+    packet/event. Destination fields are usually populated in conjuction with source fields.
   type: group
   fields:
 
diff --git a/schemas/source.yml b/schemas/source.yml
index 098df51ddc..d1dae1f71a 100644
--- a/schemas/source.yml
+++ b/schemas/source.yml
@@ -4,7 +4,7 @@
   group: 2
   description: >
     Source fields describe details about the source of a
-    packet/event.
+    packet/event. Source fields are usually populated in conjuction with destination fields.
   type: group
   fields: