diff --git a/gui/collection.c b/gui/collection.c
index f18d7b0e..6f3dfa2d 100644
--- a/gui/collection.c
+++ b/gui/collection.c
@@ -1,6 +1,9 @@
 /*
  * Copyright 2015 (c) Anna Schumaker.
  */
+#include <core/collection.h>
+#include <core/idle.h>
+#include <core/tempq.h>
 #include <gui/builder.h>
 #include <gui/collection.h>
 
@@ -15,6 +18,61 @@ enum collection_sidebar_columns {
 
 static GtkTreeModel *c_model;
 
+static void __collection_set_header(GtkTreeIter *iter, const gchar *image,
+				    GtkIconSize size,  const gchar *text)
+{
+	gtk_tree_store_set(GTK_TREE_STORE(c_model), iter, C_SB_IMAGE, image,
+			   C_SB_IMAGE_SZ, size, C_SB_PATH, text, -1);
+}
+
+static void __collection_set_library(GtkTreeIter *iter, struct library *library)
+{
+	gtk_tree_store_set(GTK_TREE_STORE(c_model), iter,
+					C_SB_ENABLED, library->li_enabled,
+					C_SB_SHOW_ENABLED, true,
+					C_SB_PATH, library->li_path,
+					C_SB_LIBRARY, library, -1);
+}
+
+static struct library *__collection_get_library(GtkTreeIter *iter)
+{
+	struct library *library;
+
+	gtk_tree_model_get(c_model, iter, C_SB_LIBRARY, &library, -1);
+	return library;
+}
+
+void __collection_add(GtkButton *button, GtkFileChooser *chooser)
+{
+	gchar *filename = gtk_file_chooser_get_filename(chooser);
+	GtkTreeIter iter, last;
+
+	gtk_tree_model_get_iter_first(c_model, &iter);
+	gtk_tree_model_iter_nth_child(c_model, &last, &iter, 0);
+	while (__collection_get_library(&last) != NULL)
+		gtk_tree_model_iter_next(c_model, &last);
+
+	gtk_tree_store_insert_before(GTK_TREE_STORE(c_model), &iter, NULL, &last);
+	__collection_set_library(&iter, collection_add(filename));
+
+	gui_collection_idle_enable();
+	g_free(filename);
+}
+
+void __collection_selection_changed(GtkTreeSelection *selection,
+				    gpointer data)
+{
+	GtkNotebook *notebook = GTK_NOTEBOOK(gui_builder_widget("o_notebook"));
+	GtkTreeIter iter;
+
+	if (gtk_tree_selection_get_selected(selection, &c_model, &iter)) {
+		if (!__collection_get_library(&iter)) {
+			gtk_notebook_set_current_page(notebook,
+						      tempq_count() + 3);
+		}
+	}
+}
+
 static gboolean __collection_select(GtkTreeSelection *selection,
 				    GtkTreeModel *model, GtkTreePath *path,
 				    gboolean selected, gpointer data)
@@ -22,23 +80,48 @@ static gboolean __collection_select(GtkTreeSelection *selection,
 	return gtk_tree_path_get_depth(path) != 1;
 }
 
+static gboolean __collection_on_idle(gpointer data)
+{
+	GtkProgressBar *progress = GTK_PROGRESS_BAR(data);
+
+	if (idle_run_task()) {
+		gtk_progress_bar_set_fraction(progress, idle_progress());
+		return G_SOURCE_CONTINUE;
+	} else {
+		gtk_widget_hide(GTK_WIDGET(progress));
+		return G_SOURCE_REMOVE;
+	}
+}
+
 void gui_collection_init()
 {
+	GtkTreeIter parent, iter;
 	GtkTreeView *treeview;
-	GtkTreeIter parent;
 
 	c_model = GTK_TREE_MODEL(gui_builder_object("o_collection_store"));
 
 	/* Add "Collection" header. */
 	gtk_tree_store_insert(GTK_TREE_STORE(c_model), &parent, NULL, -1);
-	gtk_tree_store_set(GTK_TREE_STORE(c_model), &parent,
-			   C_SB_IMAGE,    "system-file-manager",
-			   C_SB_IMAGE_SZ, GTK_ICON_SIZE_LARGE_TOOLBAR,
-			   C_SB_PATH,     "<span size='large'>Collection</span>",
-			  -1);
+	__collection_set_header(&parent, "system-file-manager",
+					 GTK_ICON_SIZE_LARGE_TOOLBAR,
+					"<span size='large'>Collection</span>");
+
+	/* Add "Add new Library" entry. */
+	gtk_tree_store_insert(GTK_TREE_STORE(c_model), &iter, &parent, -1);
+	__collection_set_header(&iter, "folder-new", GTK_ICON_SIZE_MENU,
+				"<span style='italic'>&lt;Add new path&gt;</span>");
 
 	treeview  = GTK_TREE_VIEW(gui_builder_widget("o_collection_view"));
+	gtk_tree_view_expand_all(treeview);
 	gtk_tree_selection_set_select_function(
 					gtk_tree_view_get_selection(treeview),
 					__collection_select, NULL, NULL);
 }
+
+void gui_collection_idle_enable()
+{
+	GtkWidget *progress = gui_builder_widget("o_idle_progress");
+
+	gtk_widget_show(progress);
+	g_idle_add(__collection_on_idle, progress);
+}
diff --git a/include/gui/collection.h b/include/gui/collection.h
index 8f92d948..5c0af9ac 100644
--- a/include/gui/collection.h
+++ b/include/gui/collection.h
@@ -7,4 +7,7 @@
 /* Called to initialize the GUI collection code. */
 void gui_collection_init();
 
+/* Called to enable processing idle queue tasks. */
+void gui_collection_idle_enable();
+
 #endif /* OCARINA_GUI_COLLECTION_H */
diff --git a/include/tests/gui.h b/include/tests/gui.h
index ea22c924..b4f9affc 100644
--- a/include/tests/gui.h
+++ b/include/tests/gui.h
@@ -15,4 +15,9 @@ void __audio_seek() {}
 void __sidebar_resize() {}
 #endif /* TEST_NEED_SIDEBAR */
 
+#ifdef TEST_NEED_COLLECTION
+void __collection_add() {}
+void __collection_selection_changed() {}
+#endif /* TEST_NEED_COLLECTION */
+
 #endif /* TESTS_GUI_H */
diff --git a/share/ocarina/ocarina6.glade b/share/ocarina/ocarina6.glade
index a476de0e..ac7257d7 100644
--- a/share/ocarina/ocarina6.glade
+++ b/share/ocarina/ocarina6.glade
@@ -24,6 +24,14 @@
       <mime-type>inode/directory</mime-type>
     </mime-types>
   </object>
+  <object class="GtkImage" id="image11">
+    <property name="visible">True</property>
+    <property name="can_focus">False</property>
+    <property name="xpad">5</property>
+    <property name="ypad">5</property>
+    <property name="icon_name">dialog-ok</property>
+    <property name="icon_size">3</property>
+  </object>
   <object class="GtkImage" id="image12">
     <property name="visible">True</property>
     <property name="can_focus">False</property>
@@ -621,7 +629,9 @@
                             <property name="level_indentation">10</property>
                             <property name="enable_tree_lines">True</property>
                             <child internal-child="selection">
-                              <object class="GtkTreeSelection" id="treeview-selection2"/>
+                              <object class="GtkTreeSelection" id="treeview-selection2">
+                                <signal name="changed" handler="__collection_selection_changed" swapped="no"/>
+                              </object>
                             </child>
                             <child>
                               <object class="GtkTreeViewColumn" id="treeviewcolumn1">
@@ -698,7 +708,6 @@
                             <property name="can_focus">False</property>
                             <property name="margin_left">5</property>
                             <property name="margin_right">5</property>
-                            <property name="margin_top">5</property>
                             <property name="action">select-folder</property>
                             <property name="create_folders">False</property>
                             <property name="filter">filefilter1</property>
@@ -886,11 +895,45 @@
                           <packing>
                             <property name="expand">False</property>
                             <property name="fill">True</property>
-                            <property name="padding">5</property>
                             <property name="position">1</property>
                           </packing>
                         </child>
+                        <child>
+                          <object class="GtkButtonBox" id="buttonbox3">
+                            <property name="visible">True</property>
+                            <property name="can_focus">False</property>
+                            <property name="opacity">0.96999999999999997</property>
+                            <property name="halign">center</property>
+                            <property name="layout_style">start</property>
+                            <child>
+                              <object class="GtkButton" id="button1">
+                                <property name="label" translatable="yes">Add Selected Path</property>
+                                <property name="visible">True</property>
+                                <property name="can_focus">True</property>
+                                <property name="receives_default">True</property>
+                                <property name="valign">center</property>
+                                <property name="image">image11</property>
+                                <signal name="clicked" handler="__collection_add" object="colmgr_chooser" swapped="no"/>
+                              </object>
+                              <packing>
+                                <property name="expand">True</property>
+                                <property name="fill">True</property>
+                                <property name="pack_type">end</property>
+                                <property name="position">0</property>
+                              </packing>
+                            </child>
+                          </object>
+                          <packing>
+                            <property name="expand">False</property>
+                            <property name="fill">False</property>
+                            <property name="padding">5</property>
+                            <property name="position">2</property>
+                          </packing>
+                        </child>
                       </object>
+                      <packing>
+                        <property name="tab_fill">False</property>
+                      </packing>
                     </child>
                     <child type="tab">
                       <object class="GtkBox" id="box4">
@@ -1072,7 +1115,6 @@ Manager</property>
           <object class="GtkBox" id="box12">
             <property name="visible">True</property>
             <property name="can_focus">False</property>
-            <property name="homogeneous">True</property>
             <child>
               <object class="GtkProgressBar" id="o_idle_progress">
                 <property name="can_focus">False</property>
@@ -1125,7 +1167,7 @@ Manager</property>
           </object>
           <packing>
             <property name="expand">False</property>
-            <property name="fill">True</property>
+            <property name="fill">False</property>
             <property name="padding">1</property>
             <property name="position">4</property>
           </packing>
diff --git a/tests/gui/collection.c b/tests/gui/collection.c
index b38e5921..1774f5af 100644
--- a/tests/gui/collection.c
+++ b/tests/gui/collection.c
@@ -10,16 +10,18 @@
 static void test_collection_sidebar()
 {
 	GtkTreeSelection *selection;
+	GtkTreeIter iter, child;
+	GtkNotebook *notebook;
 	GtkTreeView *treeview;
 	GtkTreeModel *model;
 	GtkTreePath *path;
-	GtkTreeIter iter;
 	int argc = 0;
 
 	gtk_init(&argc, NULL);
 	gui_builder_init("share/ocarina/ocarina6.glade");
 	gui_collection_init();
 
+	notebook  = GTK_NOTEBOOK(gui_builder_widget("o_notebook"));
 	treeview  = GTK_TREE_VIEW(gui_builder_widget("o_collection_view"));
 	selection = gtk_tree_view_get_selection(treeview);
 	model = GTK_TREE_MODEL(gui_builder_object("o_collection_store"));
@@ -28,9 +30,16 @@ static void test_collection_sidebar()
 	path = gtk_tree_model_get_path(model, &iter);
 	gtk_tree_view_set_cursor(treeview, path, NULL, false);
 	gtk_tree_path_free(path);
-
 	test_equal(gtk_tree_selection_count_selected_rows(selection), 0);
 
+	gtk_tree_model_iter_nth_child(model, &child, &iter, 0);
+	path = gtk_tree_model_get_path(model, &child);
+	gtk_tree_view_set_cursor(treeview, path, NULL, false);
+	gtk_tree_path_free(path);
+	test_equal(gtk_tree_selection_count_selected_rows(selection), 1);
+	test_equal(gtk_notebook_get_current_page(notebook),
+		   gtk_notebook_get_n_pages(notebook) - 1);
+
 	gui_builder_deinit();
 }
 
diff --git a/tests/gui/sidebar.c b/tests/gui/sidebar.c
index 6eaa0eaa..b29bdb79 100644
--- a/tests/gui/sidebar.c
+++ b/tests/gui/sidebar.c
@@ -2,6 +2,7 @@
  * Copyright 2015 (c) Anna Schumaker.
  */
 #define TEST_NEED_AUDIO
+#define TEST_NEED_COLLECTION
 #include <gui/builder.h>
 #include <gui/settings.h>
 #include <gui/sidebar.h>
diff --git a/tests/gui/window.c b/tests/gui/window.c
index b9b23637..9742bcd1 100644
--- a/tests/gui/window.c
+++ b/tests/gui/window.c
@@ -3,6 +3,7 @@
  */
 #define TEST_NEED_AUDIO
 #define TEST_NEED_SIDEBAR
+#define TEST_NEED_COLLECTION
 #include <gui/builder.h>
 #include <gui/settings.h>
 #include <gui/window.h>