diff --git a/cache/projectTemplate.xml b/cache/projectTemplate.xml
index 29881b7..5da4259 100644
--- a/cache/projectTemplate.xml
+++ b/cache/projectTemplate.xml
@@ -32,23 +32,24 @@ Return list with all namespaces</Description>
 <Description>
 Returns structured class tree with all classes available in current namespace</Description>
 <ClassMethod>1</ClassMethod>
-<FormalSpec>namespace:%String</FormalSpec>
+<FormalSpec>namespace:%String,showMapped=0</FormalSpec>
 <ReturnType>%ZEN.proxyObject</ReturnType>
 <Implementation><![CDATA[
     zn:$GET(namespace)'="" namespace
     set resp = ##class(%ZEN.proxyObject).%New()
 
-    set classes = ##class(%ResultSet).%New("%Dictionary.ClassDefinition:Summary")
+    set showSystem = (namespace="%SYS")
+    do $System.OBJ.GetClassList(.classes, "/system="_showSystem_" /percent="
+        _showSystem_" /mapped=" _ showMapped)
     set objects = ##class(%Library.ArrayOfObjects).%New()
     set lastParts = $LB()
 
     set level = 1
     do objects.SetAt(resp, level)
 
-    do classes.Execute()
-    while (classes.Next()) {
-        set name = classes.Data("Name")
-        if ($EXTRACT(name, 1, 1) = "%") && ($NAMESPACE '= "%SYS") { continue }
+	set name = $order(classes(""))
+    while (name '= "") {
+        //if ($EXTRACT(name, 1, 1) = "%") && ($NAMESPACE '= "%SYS") { continue }
         set parts = $LISTFROMSTRING(name, ".")
         set level = 1
         while ((level < $LISTLENGTH(parts)) && ($LISTGET(lastParts, level) = ("/"_$LISTGET(parts, level)))) {
@@ -67,12 +68,13 @@ Returns structured class tree with all classes available in current namespace</D
             do objects.SetAt(resp, level)
         }
         if ($LISTLENGTH(parts) = level) {
-            do resp.%DispatchSetProperty($LISTGET(parts, level), classes.Data("Hidden"))
+            do resp.%DispatchSetProperty($LISTGET(parts, level), 0)
         }
         set lastParts = parts
         for i=1:1:$LISTLENGTH(lastParts)-1 {
             set $LIST(lastParts, i) = "/"_$LISTGET(lastParts, i)
         }
+        set name = $order(classes(name))
     }
 
     quit objects.GetAt(1)
@@ -461,7 +463,7 @@ Method returns whole class tree visible in the current namespace.</Description>
 <ClassMethod>1</ClassMethod>
 <ReturnType>%Status</ReturnType>
 <Implementation><![CDATA[
-    do ##class(ClassExplorer.ClassView).getClassTree(%request.Get("namespace")).%ToJSON(, "o")
+    do ##class(ClassExplorer.ClassView).getClassTree(%request.Get("namespace"), %request.Get("mapped")).%ToJSON(, "o")
     return $$$OK
 ]]></Implementation>
 </Method>
diff --git a/package.json b/package.json
index 38ea028..91a32c3 100755
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "CacheClassExplorer",
-  "version": "1.18.1",
+  "version": "1.19.0",
   "description": "Class Explorer for InterSystems Caché",
   "directories": { "test": "test" },
   "dependencies": {},
diff --git a/web/css/treeView.css b/web/css/treeView.css
index 336c604..b01d240 100644
--- a/web/css/treeView.css
+++ b/web/css/treeView.css
@@ -16,7 +16,7 @@
     z-index: 1;
 }
 
-.ui-sideSearchBlock > input {
+.ui-sideSearchBlock input[type=search] {
     display: block;
     box-sizing: border-box;
     border: 1px solid gray;
@@ -26,6 +26,17 @@
     height: 22px;
 }
 
+.ui-sideSearchBlock label {
+    cursor: pointer;
+    user-select: none;
+    -moz-user-select: none;
+    -ms-user-select: none;
+}
+
+.ui-sideSearchBlock input[type=checkbox] {
+    vertical-align: middle;
+}
+
 .tv-package-name.minimized + .tv-package-content {
     display: none;
 }
diff --git a/web/index.html b/web/index.html
index df2362b..2b55c60 100755
--- a/web/index.html
+++ b/web/index.html
@@ -38,7 +38,15 @@
     <div class="ui-body" id="ui-body">
         <div class="ui-sideBlock">
             <div class="ui-sideSearchBlock" id="searchBlock">
-                <input type="search" id="classTreeSearch" placeholder="Search in class tree..."/>
+                <div>
+                    <label>
+                        <input type="checkbox" id="showMappedCheckbox"/>
+                        Show Mapped Classes
+                    </label>
+                </div>
+                <div>
+                    <input type="search" id="classTreeSearch" placeholder="Search in class tree..."/>
+                </div>
             </div>
             <div id="treeView">
 
diff --git a/web/js/CacheClassExplorer.js b/web/js/CacheClassExplorer.js
index 7083327..60c1f15 100755
--- a/web/js/CacheClassExplorer.js
+++ b/web/js/CacheClassExplorer.js
@@ -50,6 +50,7 @@ var CacheClassExplorer = function (treeViewContainer, classViewContainer) {
         subLabel: id("subLabel"),
         closeHelp: id("closeHelp"),
         settingsExtraText: id("settingsExtraText"),
+        showMappedCheckbox: id("showMappedCheckbox"),
         settings: {
             showDataTypesOnDiagram: id("setting.showDataTypesOnDiagram"),
             showClassIcons: id("setting.showClassIcons"),
@@ -150,16 +151,10 @@ CacheClassExplorer.prototype.updateNamespaces = function (nsData) {
  */
 CacheClassExplorer.prototype.setNamespace = function (namespace) {
 
-    var self = this;
-
     this.NAMESPACE = namespace;
     this.classTree.setSelectedClassList([]);
 
-    self.classTree.container.textContent = "";
-    self.classTree.showLoader();
-    this.source.getClassTree(function (err, data) {
-        if (!err) self.classTree.updateTree(data);
-    });
+    this.classTree.update();
 
     this.updateNamespace();
     this.updateURL();
@@ -269,9 +264,7 @@ CacheClassExplorer.prototype.init = function () {
 
     restored = this.restoreFromURL();
     this.classTree.showLoader();
-    this.source.getClassTree(function (err, data) {
-        if (!err) self.classTree.updateTree(data);
-    });
+    this.classTree.init();
     this.source.getNamespacesInfo(function (err, data) {
         if (restored && restored.namespace) data.currentNamespace = restored.namespace;
         if (!err) self.updateNamespaces(data);
diff --git a/web/js/ClassTree.js b/web/js/ClassTree.js
index 81edf70..877017c 100755
--- a/web/js/ClassTree.js
+++ b/web/js/ClassTree.js
@@ -15,6 +15,7 @@ var ClassTree = function (parent, treeViewContainer) {
     this.SELECTED_TYPE = null; // "class" || "package"
     this.SELECTED_ELEMENT = null;
 	this.SELECTED_LEVEL = null;
+	this.INCLUDE_MAPPED = this.cacheClassExplorer.elements.showMappedCheckbox.checked;
     this.treeObject = null;
     /**
      * @private
@@ -25,6 +26,10 @@ var ClassTree = function (parent, treeViewContainer) {
     this.cacheClassExplorer.elements.classTreeSearch.addEventListener("input", function (e) {
         self.searchChanged.call(self, (e.target || e.srcElement).value);
     });
+    this.cacheClassExplorer.elements.showMappedCheckbox.addEventListener("change", function () {
+        self.INCLUDE_MAPPED = self.cacheClassExplorer.elements.showMappedCheckbox.checked;
+        self.update();
+    });
 
     window.addEventListener("resize", function () {
         self.updateSizes();
@@ -34,6 +39,19 @@ var ClassTree = function (parent, treeViewContainer) {
 
 };
 
+ClassTree.prototype.update = function () {
+
+    var self = this;
+
+    this.cacheClassExplorer.elements.classTreeSearch.value = "";
+    this.container.textContent = "";
+    this.showLoader();
+    this.cacheClassExplorer.source.getClassTree(this.INCLUDE_MAPPED, function (err, data) {
+        if (!err) self.updateTree(data);
+    });
+
+};
+
 ClassTree.prototype.setSelectedClassList = function (list) {
 
     // this enables saved view to be consistent for any class names order
@@ -70,7 +88,8 @@ ClassTree.prototype.removeLoader = function () {
     if (!this.loader) return;
 
     this.cacheClassExplorer.elements.classTreeSearch.value = "";
-    this.loader.parentNode.removeChild(this.loader);
+    if (this.loader.parentNode)
+        this.loader.parentNode.removeChild(this.loader);
     this.loader = null;
 
 };
@@ -255,7 +274,7 @@ ClassTree.prototype.updateTree = function (treeObject, doNotChangeRoot) {
             arr = [];
 
         for (i in object) {
-            arr.push({ name: getRealName(i), val: object[i] });
+            arr.push({ name: getRealName(i), val: object[i], isPackage: i[0] === "/" });
         }
 
         arr.sort(function (a, b) {
@@ -268,7 +287,7 @@ ClassTree.prototype.updateTree = function (treeObject, doNotChangeRoot) {
             if (rec = append(
                     rootElement,
                     element.name,
-                    typeof element.val === "object",
+                    element.isPackage,
                     path.join("."),
                     level
                 )) {
@@ -282,4 +301,8 @@ ClassTree.prototype.updateTree = function (treeObject, doNotChangeRoot) {
 
     if (!doNotChangeRoot) this.treeObject = treeObject;
 
+};
+
+ClassTree.prototype.init = function () {
+    this.update();
 };
\ No newline at end of file
diff --git a/web/js/Source.js b/web/js/Source.js
index a0fc2f7..9f78e25 100755
--- a/web/js/Source.js
+++ b/web/js/Source.js
@@ -9,13 +9,15 @@ var Source = function (cacheUMLExplorer) {
 
 /**
  * Return class tree.
+ * @param {boolean} includeMapped
  * @param {Source~dataCallback} callback
  */
-Source.prototype.getClassTree = function (callback) {
+Source.prototype.getClassTree = function (includeMapped, callback) {
 
     lib.load(
         this.URL + "/GetClassTree"
-            + (this.cue.NAMESPACE ? "?namespace=" + encodeURIComponent(this.cue.NAMESPACE) : ""),
+            + (this.cue.NAMESPACE ? "?namespace=" + encodeURIComponent(this.cue.NAMESPACE) : "")
+            + "&mapped=" + (includeMapped ? "1" : "0"),
         null,
         callback
     );