diff --git a/source/MaterialXGraphEditor/CMakeLists.txt b/source/MaterialXGraphEditor/CMakeLists.txt
index 15547de47d..1785540bd8 100644
--- a/source/MaterialXGraphEditor/CMakeLists.txt
+++ b/source/MaterialXGraphEditor/CMakeLists.txt
@@ -19,6 +19,11 @@ endif()
 file(GLOB materialx_source "${CMAKE_CURRENT_SOURCE_DIR}/*.cpp")
 file(GLOB materialx_headers "${CMAKE_CURRENT_SOURCE_DIR}/*.h*")
 
+if (APPLE)
+    list(APPEND materialx_source ${CMAKE_CURRENT_SOURCE_DIR}/FileDialog.mm)
+    set_source_files_properties("${CMAKE_CURRENT_SOURCE_DIR}/FileDialog.mm" PROPERTIES LANGUAGE CXX)
+endif ()
+
 file(GLOB imgui_source "${DEAR_IMGUI_PREFIX}/*.cpp")
 file(GLOB imgui_headers "${DEAR_IMGUI_PREFIX}/*.h*")
 
@@ -49,7 +54,6 @@ include_directories("${DEAR_IMGUI_PREFIX}/backends")
 include_directories("${DEAR_IMGUI_PREFIX}/misc/cpp")
 include_directories("${CMAKE_CURRENT_SOURCE_DIR}/External/ImGuiNodeEditor")
 include_directories("${CMAKE_CURRENT_SOURCE_DIR}/External/ImGuiNodeEditor/examples/blueprints-example/utilities")
-include_directories("${CMAKE_CURRENT_SOURCE_DIR}/External/ImGuiFileBrowser")
 
 set(GLFW_BUILD_EXAMPLES OFF)
 set(GLFW_BUILD_TESTS OFF)
@@ -75,6 +79,11 @@ set(MATERIALX_LIBRARIES
     MaterialXGenGlsl
     MaterialXRenderGlsl)
 
+if (APPLE)
+    find_library(CORE_FOUNDATION Foundation REQUIRED)
+    list(APPEND MATERIALX_LIBRARIES ${CORE_FOUNDATION})
+endif ()
+
 target_link_libraries(
     MaterialXGraphEditor
     PRIVATE
diff --git a/source/MaterialXGraphEditor/FileDialog.cpp b/source/MaterialXGraphEditor/FileDialog.cpp
new file mode 100644
index 0000000000..263c5706b4
--- /dev/null
+++ b/source/MaterialXGraphEditor/FileDialog.cpp
@@ -0,0 +1,244 @@
+//
+// Copyright Contributors to the MaterialX Project
+// SPDX-License-Identifier: Apache-2.0
+//
+
+#include "FileDialog.h"
+
+#include <MaterialXCore/Exception.h>
+
+#if defined(_WIN32)
+    #include <windows.h>
+#endif
+
+FileDialog::FileDialog(int flags) :
+    _flags(flags)
+{
+}
+
+void FileDialog::setTitle(const std::string& title)
+{
+    _title = title;
+}
+
+void FileDialog::setTypeFilters(const mx::StringVec& typeFilters)
+{
+    _filetypes.clear();
+
+    for (auto typefilter : typeFilters)
+    {
+        std::string minus_ext = typefilter.substr(1, typefilter.size() - 1);
+        std::pair<std::string, std::string> filterPair = { minus_ext, minus_ext };
+        _filetypes.push_back(filterPair);
+    }
+}
+
+void FileDialog::open()
+{
+    clearSelected();
+    _openFlag = true;
+}
+
+bool FileDialog::isOpened()
+{
+    return _isOpened;
+}
+
+bool FileDialog::hasSelected()
+{
+    return !_selectedFilenames.empty();
+}
+
+mx::FilePath FileDialog::getSelected()
+{
+    if (_selectedFilenames.empty())
+    {
+        return {};
+    }
+
+    return *_selectedFilenames.begin();
+}
+
+void FileDialog::clearSelected()
+{
+    _selectedFilenames.clear();
+}
+
+void FileDialog::display()
+{
+    // Only call the dialog if it's not already displayed
+    if (!_openFlag || _isOpened)
+    {
+        return;
+    }
+    _openFlag = false;
+
+    // Check if we want to save or open
+    bool save = !(_flags & FileDialogFlags_SelectDirectory) &&
+                (_flags & FileDialogFlags_EnterNewFilename);
+
+    std::string path = launchFileDialog(_filetypes, save);
+    if (!path.empty())
+    {
+        _selectedFilenames.push_back(path);
+    }
+
+    _isOpened = false;
+}
+
+std::string launchFileDialog(const std::vector<std::pair<std::string, std::string>>& filetypes, bool save)
+{
+    mx::StringVec result = launchFileDialog(filetypes, save, false);
+    return result.empty() ? "" : result.front();
+}
+
+#if !defined(__APPLE__)
+mx::StringVec launchFileDialog(const std::vector<std::pair<std::string, std::string>>& filetypes, bool save, bool multiple)
+{
+    static const int FILE_DIALOG_MAX_BUFFER = 16384;
+    if (save && multiple)
+    {
+        throw mx::Exception("save and multiple must not both be true.");
+    }
+
+    #if defined(_WIN32)
+    OPENFILENAME ofn;
+    ZeroMemory(&ofn, sizeof(OPENFILENAME));
+    ofn.lStructSize = sizeof(OPENFILENAME);
+    char tmp[FILE_DIALOG_MAX_BUFFER];
+    ofn.lpstrFile = tmp;
+    ZeroMemory(tmp, FILE_DIALOG_MAX_BUFFER);
+    ofn.nMaxFile = FILE_DIALOG_MAX_BUFFER;
+    ofn.nFilterIndex = 1;
+
+    std::string filter;
+
+    if (!save && filetypes.size() > 1)
+    {
+        filter.append("Supported file types (");
+        for (size_t i = 0; i < filetypes.size(); ++i)
+        {
+            filter.append("*.");
+            filter.append(filetypes[i].first);
+            if (i + 1 < filetypes.size())
+                filter.append(";");
+        }
+        filter.append(")");
+        filter.push_back('\0');
+        for (size_t i = 0; i < filetypes.size(); ++i)
+        {
+            filter.append("*.");
+            filter.append(filetypes[i].first);
+            if (i + 1 < filetypes.size())
+                filter.append(";");
+        }
+        filter.push_back('\0');
+    }
+    for (auto pair : filetypes)
+    {
+        filter.append(pair.second);
+        filter.append(" (*.");
+        filter.append(pair.first);
+        filter.append(")");
+        filter.push_back('\0');
+        filter.append("*.");
+        filter.append(pair.first);
+        filter.push_back('\0');
+    }
+    filter.push_back('\0');
+    ofn.lpstrFilter = filter.data();
+
+    if (save)
+    {
+        ofn.Flags = OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_OVERWRITEPROMPT;
+        if (GetSaveFileNameA(&ofn) == FALSE)
+            return {};
+    }
+    else
+    {
+        ofn.Flags = OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST;
+        if (multiple)
+            ofn.Flags |= OFN_ALLOWMULTISELECT;
+        if (GetOpenFileNameA(&ofn) == FALSE)
+            return {};
+    }
+
+    size_t i = 0;
+    mx::StringVec result;
+    while (tmp[i] != '\0')
+    {
+        result.emplace_back(&tmp[i]);
+        i += result.back().size() + 1;
+    }
+
+    if (result.size() > 1)
+    {
+        for (i = 1; i < result.size(); ++i)
+        {
+            result[i] = result[0] + "\\" + result[i];
+        }
+        result.erase(begin(result));
+    }
+
+    if (save && ofn.nFilterIndex > 0)
+    {
+        auto ext = filetypes[ofn.nFilterIndex - 1].first;
+        if (ext != "*")
+        {
+            ext.insert(0, ".");
+
+            auto& name = result.front();
+            if (name.size() <= ext.size() ||
+                name.compare(name.size() - ext.size(), ext.size(), ext) != 0)
+            {
+                name.append(ext);
+            }
+        }
+    }
+
+    return result;
+    #else
+    char buffer[FILE_DIALOG_MAX_BUFFER];
+    buffer[0] = '\0';
+
+    std::string cmd = "zenity --file-selection ";
+    // The safest separator for multiple selected paths is /, since / can never occur
+    // in file names. Only where two paths are concatenated will there be two / following
+    // each other.
+    if (multiple)
+        cmd += "--multiple --separator=\"/\" ";
+    if (save)
+        cmd += "--save ";
+    cmd += "--file-filter=\"";
+    for (auto pair : filetypes)
+        cmd += "\"*." + pair.first + "\" ";
+    cmd += "\"";
+    FILE* output = popen(cmd.c_str(), "r");
+    if (output == nullptr)
+        throw mx::Exception("popen() failed -- could not launch zenity!");
+    while (fgets(buffer, FILE_DIALOG_MAX_BUFFER, output) != NULL)
+        ;
+    pclose(output);
+    std::string paths(buffer);
+    paths.erase(std::remove(paths.begin(), paths.end(), '\n'), paths.end());
+
+    mx::StringVec result;
+    while (!paths.empty())
+    {
+        size_t end = paths.find("//");
+        if (end == std::string::npos)
+        {
+            result.emplace_back(paths);
+            paths = "";
+        }
+        else
+        {
+            result.emplace_back(paths.substr(0, end));
+            paths = paths.substr(end + 1);
+        }
+    }
+
+    return result;
+    #endif
+}
+#endif
diff --git a/source/MaterialXGraphEditor/FileDialog.h b/source/MaterialXGraphEditor/FileDialog.h
new file mode 100644
index 0000000000..dd8750e53b
--- /dev/null
+++ b/source/MaterialXGraphEditor/FileDialog.h
@@ -0,0 +1,51 @@
+//
+// Copyright Contributors to the MaterialX Project
+// SPDX-License-Identifier: Apache-2.0
+//
+
+#ifndef MATERIALX_FILEDIALOG_H
+#define MATERIALX_FILEDIALOG_H
+
+#include <MaterialXFormat/File.h>
+
+namespace mx = MaterialX;
+
+enum FileDialogFlags
+{
+    FileDialogFlags_SelectDirectory   = 1 << 0, // select directory instead of regular file
+    FileDialogFlags_EnterNewFilename  = 1 << 1, // allow user to enter new filename when selecting regular file
+    FileDialogFlags_NoModal           = 1 << 2, // file browsing window is modal by default. specify this to use a popup window
+    FileDialogFlags_NoTitleBar        = 1 << 3, // hide window title bar
+    FileDialogFlags_NoStatusBar       = 1 << 4, // hide status bar at the bottom of browsing window
+    FileDialogFlags_CloseOnEsc        = 1 << 5, // close file browser when pressing 'ESC'
+    FileDialogFlags_CreateNewDir      = 1 << 6, // allow user to create new directory
+    FileDialogFlags_MultipleSelection = 1 << 7, // allow user to select multiple files. this will hide FileDialogFlags_EnterNewFilename
+};
+
+// A native file browser class, based on the implementation in NanoGUI.
+class FileDialog
+{
+  public:
+    FileDialog(int flags = 0);
+    void setTitle(const std::string& title);
+    void setTypeFilters(const mx::StringVec& typeFilters);
+    void open();
+    bool isOpened();
+    void display();
+    bool hasSelected();
+    mx::FilePath getSelected();
+    void clearSelected();
+
+  private:
+    int _flags;
+    std::string _title;
+    bool _openFlag = false;
+    bool _isOpened = false;
+    std::vector<mx::FilePath> _selectedFilenames;
+    std::vector<std::pair<std::string, std::string>> _filetypes;
+};
+
+std::string launchFileDialog(const std::vector<std::pair<std::string, std::string>>& filetypes, bool save);
+mx::StringVec launchFileDialog(const std::vector<std::pair<std::string, std::string>>& filetypes, bool save, bool multiple);
+
+#endif
diff --git a/source/MaterialXGraphEditor/FileDialog.mm b/source/MaterialXGraphEditor/FileDialog.mm
new file mode 100644
index 0000000000..5e2af40d5b
--- /dev/null
+++ b/source/MaterialXGraphEditor/FileDialog.mm
@@ -0,0 +1,55 @@
+//
+// Copyright Contributors to the MaterialX Project
+// SPDX-License-Identifier: Apache-2.0
+//
+
+#include "FileDialog.h"
+
+#include <MaterialXCore/Exception.h>
+
+#import <Cocoa/Cocoa.h>
+
+mx::StringVec launchFileDialog(const std::vector<std::pair<std::string, std::string>>& filetypes, bool save, bool multiple)
+{
+    if (save && multiple)
+    {
+        throw mx::Exception("launchFileDialog(): 'save' and 'multiple' must not both be true.");
+    }
+
+    mx::StringVec result;
+    if (save)
+    {
+        NSSavePanel* saveDlg = [NSSavePanel savePanel];
+
+        NSMutableArray* types = [NSMutableArray new];
+        for (size_t idx = 0; idx < filetypes.size(); ++idx)
+            [types addObject:[NSString stringWithUTF8String:filetypes[idx].first.c_str()]];
+
+        [saveDlg setAllowedFileTypes:types];
+
+        if ([saveDlg runModal] == NSModalResponseOK)
+            result.emplace_back([[[saveDlg URL] path] UTF8String]);
+    }
+    else
+    {
+        NSOpenPanel* openDlg = [NSOpenPanel openPanel];
+
+        [openDlg setCanChooseFiles:YES];
+        [openDlg setCanChooseDirectories:NO];
+        [openDlg setAllowsMultipleSelection:multiple];
+        NSMutableArray* types = [NSMutableArray new];
+        for (size_t idx = 0; idx < filetypes.size(); ++idx)
+            [types addObject:[NSString stringWithUTF8String:filetypes[idx].first.c_str()]];
+
+        [openDlg setAllowedFileTypes:types];
+
+        if ([openDlg runModal] == NSModalResponseOK)
+        {
+            for (NSURL* url in [openDlg URLs])
+            {
+                result.emplace_back((char*) [[url path] UTF8String]);
+            }
+        }
+    }
+    return result;
+}
diff --git a/source/MaterialXGraphEditor/Graph.cpp b/source/MaterialXGraphEditor/Graph.cpp
index fba8958c11..dddd9d0d54 100644
--- a/source/MaterialXGraphEditor/Graph.cpp
+++ b/source/MaterialXGraphEditor/Graph.cpp
@@ -47,7 +47,7 @@ Graph::Graph(const std::string& materialFilename,
     _libraryFolders(libraryFolders),
     _initial(false),
     _delete(false),
-    _fileDialogSave(ImGuiFileBrowserFlags_EnterNewFilename | ImGuiFileBrowserFlags_CreateNewDir),
+    _fileDialogSave(FileDialogFlags_EnterNewFilename | FileDialogFlags_CreateNewDir),
     _isNodeGraph(false),
     _graphTotalSize(0),
     _popup(false),
@@ -1018,9 +1018,9 @@ void Graph::setConstant(UiNodePtr node, mx::InputPtr& input, const mx::UIPropert
             // browser button to select new file
             if (ImGui::Button("Browse"))
             {
-                _fileDialogImage.SetTitle("Node Input Dialog");
-                _fileDialogImage.Open();
-                _fileDialogImage.SetTypeFilters(_imageFilter);
+                _fileDialogImage.setTitle("Node Input Dialog");
+                _fileDialogImage.open();
+                _fileDialogImage.setTypeFilters(_imageFilter);
             }
             ImGui::SameLine();
             ImGui::PushItemWidth(labelWidth);
@@ -1030,15 +1030,15 @@ void Graph::setConstant(UiNodePtr node, mx::InputPtr& input, const mx::UIPropert
             ImGui::PopStyleColor();
 
             // create and load document from selected file
-            if (_fileDialogImage.HasSelected())
+            if (_fileDialogImage.hasSelected())
             {
                 // set the new filename to the complete file path
-                mx::FilePath fileName = mx::FilePath(_fileDialogImage.GetSelected().string());
+                mx::FilePath fileName = _fileDialogImage.getSelected();
                 temp = fileName;
                 // need to set the file prefix for the input to "" so that it can find the new file
                 input->setAttribute(input->FILE_PREFIX_ATTRIBUTE, "");
-                _fileDialogImage.ClearSelected();
-                _fileDialogImage.SetTypeFilters(std::vector<std::string>());
+                _fileDialogImage.clearSelected();
+                _fileDialogImage.setTypeFilters(std::vector<std::string>());
             }
 
             // set input value  and update materials if different from previous value
@@ -2884,23 +2884,23 @@ void Graph::loadGraphFromFile()
         _currUiNode = nullptr;
     }
 
-    _fileDialog.SetTitle("Open File");
-    _fileDialog.SetTypeFilters(_mtlxFilter);
-    _fileDialog.Open();
+    _fileDialog.setTitle("Open File");
+    _fileDialog.setTypeFilters(_mtlxFilter);
+    _fileDialog.open();
 }
 
 void Graph::saveGraphToFile()
 {
-    _fileDialogSave.SetTypeFilters(_mtlxFilter);
-    _fileDialogSave.SetTitle("Save File As");
-    _fileDialogSave.Open();
+    _fileDialogSave.setTypeFilters(_mtlxFilter);
+    _fileDialogSave.setTitle("Save File As");
+    _fileDialogSave.open();
 }
 
 void Graph::loadGeometry()
 {
-    _fileDialogGeom.SetTitle("Load Geometry");
-    _fileDialogGeom.SetTypeFilters(_geomFilter);
-    _fileDialogGeom.Open();
+    _fileDialogGeom.setTitle("Load Geometry");
+    _fileDialogGeom.setTypeFilters(_geomFilter);
+    _fileDialogGeom.open();
 }
 
 void Graph::graphButtons()
@@ -2962,7 +2962,7 @@ void Graph::graphButtons()
 
     // Menu keys
     ImGuiIO& guiIO = ImGui::GetIO();
-    if (guiIO.KeyCtrl && !_fileDialogSave.IsOpened() && !_fileDialog.IsOpened() && !_fileDialogGeom.IsOpened())
+    if (guiIO.KeyCtrl && !_fileDialogSave.isOpened() && !_fileDialog.isOpened() && !_fileDialogGeom.isOpened())
     {
         if (ImGui::IsKeyReleased(ImGuiKey_O))
         {
@@ -3551,7 +3551,7 @@ void Graph::handleRenderViewInputs(ImVec2 minValue, float width, float height)
             _renderer->setKeyEvent(ImGuiKey_KeypadSubtract);
         }
         // scrolling not possible if open or save file dialog is open
-        if (scrollAmt != 0 && !_fileDialogSave.IsOpened() && !_fileDialog.IsOpened() && !_fileDialogGeom.IsOpened())
+        if (scrollAmt != 0 && !_fileDialogSave.isOpened() && !_fileDialog.isOpened() && !_fileDialogGeom.isOpened())
         {
             _renderer->setScrollEvent(scrollAmt);
         }
@@ -3795,13 +3795,13 @@ void Graph::drawGraph(ImVec2 mousePos)
         }
 
         // hotkey to frame selected node(s)
-        if (ImGui::IsKeyReleased(ImGuiKey_F) && !_fileDialogSave.IsOpened())
+        if (ImGui::IsKeyReleased(ImGuiKey_F) && !_fileDialogSave.isOpened())
         {
             ed::NavigateToSelection();
         }
 
         // go back up from inside a subgraph
-        if (ImGui::IsKeyReleased(ImGuiKey_U) && (!ImGui::IsPopupOpen("add node")) && (!ImGui::IsPopupOpen("search")) && !_fileDialogSave.IsOpened())
+        if (ImGui::IsKeyReleased(ImGuiKey_U) && (!ImGui::IsPopupOpen("add node")) && (!ImGui::IsPopupOpen("search")) && !_fileDialogSave.isOpened())
         {
             upNodeGraph();
         }
@@ -3929,9 +3929,9 @@ void Graph::drawGraph(ImVec2 mousePos)
     }
 
     ed::Suspend();
-    _fileDialogSave.Display();
+    _fileDialogSave.display();
     // saving file
-    if (_fileDialogSave.HasSelected())
+    if (_fileDialogSave.hasSelected())
     {
 
         std::string message;
@@ -3940,13 +3940,13 @@ void Graph::drawGraph(ImVec2 mousePos)
             std::cerr << "*** Validation warnings for " << _materialFilename.getBaseName() << " ***" << std::endl;
             std::cerr << message;
         }
-        std::string fileName = _fileDialogSave.GetSelected().string();
-        mx::FilePath name = _fileDialogSave.GetSelected().string();
+        std::string fileName = _fileDialogSave.getSelected();
+        mx::FilePath name = _fileDialogSave.getSelected();
         ed::Resume();
         savePosition();
 
         writeText(fileName, name);
-        _fileDialogSave.ClearSelected();
+        _fileDialogSave.clearSelected();
     }
     else
     {
@@ -3956,11 +3956,11 @@ void Graph::drawGraph(ImVec2 mousePos)
     ed::End();
     ImGui::End();
 
-    _fileDialog.Display();
+    _fileDialog.display();
     // create and load document from selected file
-    if (_fileDialog.HasSelected())
+    if (_fileDialog.hasSelected())
     {
-        mx::FilePath fileName = mx::FilePath(_fileDialog.GetSelected().string());
+        mx::FilePath fileName = _fileDialog.getSelected();
         _currGraphName.clear();
         std::string graphName = fileName.getBaseName();
         _currGraphName.push_back(graphName.substr(0, graphName.length() - 5));
@@ -3971,22 +3971,22 @@ void Graph::drawGraph(ImVec2 mousePos)
         buildUiBaseGraph(_graphDoc);
         _currGraphElem = _graphDoc;
         _prevUiNode = nullptr;
-        _fileDialog.ClearSelected();
+        _fileDialog.clearSelected();
 
         _renderer->setDocument(_graphDoc);
         _renderer->updateMaterials(nullptr);
     }
 
-    _fileDialogGeom.Display();
-    if (_fileDialogGeom.HasSelected())
+    _fileDialogGeom.display();
+    if (_fileDialogGeom.hasSelected())
     {
-        mx::FilePath fileName = mx::FilePath(_fileDialogGeom.GetSelected().string());
-        _fileDialogGeom.ClearSelected();
+        mx::FilePath fileName = _fileDialogGeom.getSelected();
+        _fileDialogGeom.clearSelected();
         _renderer->loadMesh(fileName);
         _renderer->updateMaterials(nullptr);
     }
 
-    _fileDialogImage.Display();
+    _fileDialogImage.display();
 }
 
 // return node location in graphNodes vector based off of node id
diff --git a/source/MaterialXGraphEditor/Graph.h b/source/MaterialXGraphEditor/Graph.h
index 2a27b5702f..bb56a06ab0 100644
--- a/source/MaterialXGraphEditor/Graph.h
+++ b/source/MaterialXGraphEditor/Graph.h
@@ -6,13 +6,11 @@
 #ifndef MATERIALX_GRAPH_H
 #define MATERIALX_GRAPH_H
 
+#include <MaterialXGraphEditor/FileDialog.h>
 #include <MaterialXGraphEditor/RenderView.h>
 #include <MaterialXGraphEditor/UiNode.h>
 
-#include <MaterialXFormat/File.h>
-
 #include <imgui_node_editor.h>
-#include <imfilebrowser.h>
 
 #include <stack>
 
@@ -212,10 +210,11 @@ class Graph
     bool _delete;
 
     // file dialog information
-    ImGui::FileBrowser _fileDialog;
-    ImGui::FileBrowser _fileDialogSave;
-    ImGui::FileBrowser _fileDialogImage;
-    ImGui::FileBrowser _fileDialogGeom;
+    FileDialog _fileDialog;
+    FileDialog _fileDialogSave;
+    FileDialog _fileDialogImage;
+    FileDialog _fileDialogGeom;
+
 
     bool _isNodeGraph;