diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index 6437ecab7..2994c3573 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -77,6 +77,10 @@ bool Particle::update(float frameTime) {
   return (life>0);
 }
 
+void centerNextWindow(float w, float h) {
+  ImGui::SetNextWindowPos(ImVec2(w*0.5,h*0.5),ImGuiCond_Always,ImVec2(0.5,0.5));
+}
+
 void FurnaceGUI::bindEngine(DivEngine* eng) {
   e=eng;
   wavePreview.setEngine(e);
@@ -4526,6 +4530,7 @@ bool FurnaceGUI::loop() {
       ImGui::OpenPopup("System File Dialog Pending");
     }
 
+    centerNextWindow(canvasW,canvasH);
     if (ImGui::BeginPopupModal("System File Dialog Pending",NULL,ImGuiWindowFlags_NoTitleBar|ImGuiWindowFlags_NoBackground|ImGuiWindowFlags_NoResize|ImGuiWindowFlags_NoMove)) {
       if (!fileDialog->isOpen()) {
         ImGui::CloseCurrentPopup();
@@ -5194,6 +5199,7 @@ bool FurnaceGUI::loop() {
 
     MEASURE_BEGIN(popup);
 
+    centerNextWindow(canvasW,canvasH);
     if (ImGui::BeginPopupModal("Rendering...",NULL,ImGuiWindowFlags_AlwaysAutoResize)) {
       ImGui::Text("Please wait...");
       if (ImGui::Button("Abort")) {
@@ -5221,6 +5227,7 @@ bool FurnaceGUI::loop() {
       ImGui::EndPopup();
     }
 
+    centerNextWindow(canvasW,canvasH);
     if (ImGui::BeginPopupModal("Error",NULL,ImGuiWindowFlags_AlwaysAutoResize)) {
       ImGui::Text("%s",errorString.c_str());
       if (ImGui::Button("OK")) {
@@ -5229,6 +5236,7 @@ bool FurnaceGUI::loop() {
       ImGui::EndPopup();
     }
 
+    centerNextWindow(canvasW,canvasH);
     if (ImGui::BeginPopupModal("Warning",NULL,ImGuiWindowFlags_AlwaysAutoResize)) {
       ImGui::Text("%s",warnString.c_str());
       switch (warnAction) {
@@ -5597,6 +5605,7 @@ bool FurnaceGUI::loop() {
     // TODO:
     // - multiple selection
     // - replace instrument
+    centerNextWindow(canvasW,canvasH);
     if (ImGui::BeginPopupModal("Select Instrument",NULL,ImGuiWindowFlags_AlwaysAutoResize)) {
       bool quitPlease=false;
       if (pendingInsSingle) {
@@ -5674,6 +5683,7 @@ bool FurnaceGUI::loop() {
       ImGui::EndPopup();
     }
 
+    centerNextWindow(canvasW,canvasH);
     if (ImGui::BeginPopupModal("Import Raw Sample",NULL,ImGuiWindowFlags_AlwaysAutoResize)) {
       ImGui::Text("Data type:");
       for (int i=0; i<DIV_SAMPLE_DEPTH_MAX; i++) {