diff --git a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/FormatUtilities.java b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/FormatUtilities.java
index 91dcf9622..8cea98eb4 100644
--- a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/FormatUtilities.java
+++ b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/FormatUtilities.java
@@ -80,7 +80,11 @@ public abstract class FormatUtilities {
   public static final String XHTML_NS = "http://www.w3.org/1999/xhtml";
   public static final String NS_XSI = "http://www.w3.org/2001/XMLSchema-instance";
   private static final int MAX_SCAN_LENGTH = 1000; // how many characters to scan into content when autodetermining format
- 
+  
+  public static final String MAP_ATTRIBUTE_NAME = "mapAttribute";
+  public static final String PROPERTY_NAME = "property";
+  public static String WORKING_CM_PROP_NAME = PROPERTY_NAME;
+  
   protected String toString(String value) {
     return value;
   }
diff --git a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/JsonParser.java b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/JsonParser.java
index 0d63655c0..11c998e02 100644
--- a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/JsonParser.java
+++ b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/JsonParser.java
@@ -9418,10 +9418,10 @@ public class JsonParser extends JsonParserBase {
 
   protected void parseConceptMapOtherElementComponentProperties(JsonObject json, ConceptMap.OtherElementComponent res) throws IOException, FHIRFormatError {
     parseBackboneElementProperties(json, res);
-    if (json.has("property"))
-      res.setPropertyElement(parseUri(json.get("property").getAsString()));
-    if (json.has("_property"))
-      parseElementProperties(getJObject(json, "_property"), res.getPropertyElement());
+    if (json.has(FormatUtilities.WORKING_CM_PROP_NAME))
+      res.setPropertyElement(parseUri(json.get(FormatUtilities.WORKING_CM_PROP_NAME).getAsString()));
+    if (json.has("_"+FormatUtilities.WORKING_CM_PROP_NAME))
+      parseElementProperties(getJObject(json, "_"+FormatUtilities.WORKING_CM_PROP_NAME), res.getPropertyElement());
     DataType value = parseType("value", json);
     if (value != null)
       res.setValue(value);
@@ -44920,8 +44920,8 @@ public class JsonParser extends JsonParserBase {
   protected void composeOtherElementComponentProperties(ConceptMap.OtherElementComponent element) throws IOException {
     composeBackboneElementProperties(element);
       if (element.hasPropertyElement()) {
-        composeUriCore("property", element.getPropertyElement(), false);
-        composeUriExtras("property", element.getPropertyElement(), false);
+        composeUriCore(FormatUtilities.WORKING_CM_PROP_NAME, element.getPropertyElement(), false);
+        composeUriExtras(FormatUtilities.WORKING_CM_PROP_NAME, element.getPropertyElement(), false);
       }
       if (element.hasValue()) {
         composeType("value", element.getValue());
diff --git a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/XmlParser.java b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/XmlParser.java
index acb18bb8c..488c9d41a 100644
--- a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/XmlParser.java
+++ b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/formats/XmlParser.java
@@ -8204,7 +8204,7 @@ public class XmlParser extends XmlParserBase {
   }
 
   protected boolean parseConceptMapOtherElementComponentContent(int eventType, XmlPullParser xpp, ConceptMap.OtherElementComponent res) throws XmlPullParserException, IOException, FHIRFormatError {
-    if (eventType == XmlPullParser.START_TAG && xpp.getName().equals("property")) {
+    if (eventType == XmlPullParser.START_TAG && xpp.getName().equals(FormatUtilities.WORKING_CM_PROP_NAME)) {
       res.setPropertyElement(parseUri(xpp));
     } else if (eventType == XmlPullParser.START_TAG && nameIsTypeName(xpp, "value")) {
       res.setValue(parseType("value", xpp));
@@ -38972,7 +38972,7 @@ public class XmlParser extends XmlParserBase {
   protected void composeConceptMapOtherElementComponentElements(ConceptMap.OtherElementComponent element) throws IOException {
     composeBackboneElementElements(element);
     if (element.hasPropertyElement()) {
-      composeUri("property", element.getPropertyElement());
+      composeUri(FormatUtilities.WORKING_CM_PROP_NAME, element.getPropertyElement());
     }
     if (element.hasValue()) {
       composeType("value", element.getValue());
diff --git a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/renderers/ConceptMapRenderer.java b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/renderers/ConceptMapRenderer.java
index ef8f00e36..d2e959539 100644
--- a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/renderers/ConceptMapRenderer.java
+++ b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/renderers/ConceptMapRenderer.java
@@ -212,7 +212,7 @@ public class ConceptMapRenderer extends TerminologyRenderer {
         } else
           tr.td().b().tx("Code");
         for (String s : sources.keySet()) {
-          if (!s.equals("code")) {
+          if (s != null && !s.equals("code")) {
             if (sources.get(s).size() == 1) {
               String url = sources.get(s).iterator().next();
               renderCSDetailsLink(tr, url, false);           
@@ -229,7 +229,7 @@ public class ConceptMapRenderer extends TerminologyRenderer {
         } else
           tr.td().b().tx("Code");
         for (String s : targets.keySet()) {
-          if (!s.equals("code")) {
+          if (s != null && !s.equals("code")) {
             if (targets.get(s).size() == 1) {
               String url = targets.get(s).iterator().next();
               renderCSDetailsLink(tr, url, false);           
@@ -291,7 +291,7 @@ public class ConceptMapRenderer extends TerminologyRenderer {
                   td.style("border-top-style: none; border-left-width: 0px");
               }
               for (String s : sources.keySet()) {
-                if (!s.equals("code")) {
+                if (s != null && !s.equals("code")) {
                   td = tr.td();
                   if (first) {
                     td.addText(getValue(ccm.getDependsOn(), s, sources.get(s).size() != 1));
@@ -323,7 +323,7 @@ public class ConceptMapRenderer extends TerminologyRenderer {
               tr.td().style("border-left-width: 0px").tx(display == null ? "" : display);
 
               for (String s : targets.keySet()) {
-                if (!s.equals("code")) {
+                if (s != null && !s.equals("code")) {
                   td = tr.td();
                   td.addText(getValue(ccm.getProduct(), s, targets.get(s).size() != 1));
                   display = getDisplay(ccm.getProduct(), s);