diff --git a/crates/opensi-editor/src/app.rs b/crates/opensi-editor/src/app.rs
index 170fb10..523555c 100644
--- a/crates/opensi-editor/src/app.rs
+++ b/crates/opensi-editor/src/app.rs
@@ -1,6 +1,9 @@
+use opensi_core::PackageNode;
+
 use crate::{
     file_dialogs::{self, LoadingPackageReceiver},
     package_tree::{self},
+    workarea,
 };
 
 const FONT_REGULAR_ID: &'static str = "Regular";
@@ -63,7 +66,7 @@ impl eframe::App for EditorApp {
                         ui.close_menu();
                     }
                     if ui.button("💾 Сохранить").clicked() {
-                        let PackageState::Active(ref package) = self.package_state else {
+                        let PackageState::Active { ref package, .. } = self.package_state else {
                             return;
                         };
                         file_dialogs::export_dialog(package);
@@ -77,7 +80,7 @@ impl eframe::App for EditorApp {
                         }
                     }
                 });
-                if let PackageState::Active(ref _package) = self.package_state {
+                if let PackageState::Active { .. } = self.package_state {
                     ui.menu_button("Пак", |ui| {
                         if ui.button("❌Закрыть").clicked() {
                             self.package_state = PackageState::None;
@@ -88,28 +91,31 @@ impl eframe::App for EditorApp {
             });
         });
 
-        egui::SidePanel::left("question-tree").min_width(200.0).show(ctx, |ui| {
-            match self.package_state {
-                PackageState::Active(ref mut package) => {
-                    package_tree::package_tree(package, ui);
-                },
-                _ => {
-                    ui.weak("Пак не выбран");
-                },
-            }
-        });
+        if let PackageState::Active { package, selected } = &mut self.package_state {
+            egui::SidePanel::left("question-tree").min_width(200.0).show(ctx, |ui| {
+                package_tree::package_tree(package, selected, ui);
+            });
+        }
 
-        egui::CentralPanel::default().show(ctx, |ui| {
-            ui.with_layout(
-                egui::Layout::centered_and_justified(egui::Direction::LeftToRight),
-                |ui| {
-                    let text = egui::RichText::new("We're so back")
-                        .size(100.0)
-                        .color(ui.style().visuals.weak_text_color());
-                    ui.add(egui::Label::new(text));
-                },
-            );
-        });
+        egui::CentralPanel::default()
+            .frame(egui::Frame::central_panel(&ctx.style()).inner_margin(16.0))
+            .show(ctx, |ui| {
+                ui.with_layout(
+                    egui::Layout::centered_and_justified(egui::Direction::LeftToRight),
+                    |ui| {
+                        if let PackageState::Active { package, selected } = &mut self.package_state
+                        {
+                            workarea::workarea(package, selected, ui);
+                        } else {
+                            let text = egui::RichText::new("OpenSI Editor")
+                                .italics()
+                                .size(64.0)
+                                .color(ui.style().visuals.weak_text_color());
+                            ui.add(egui::Label::new(text).selectable(false));
+                        }
+                    },
+                );
+            });
     }
 }
 
@@ -119,7 +125,10 @@ enum PackageState {
     None,
     #[serde(skip)]
     Loading(LoadingPackageReceiver),
-    Active(opensi_core::Package),
+    Active {
+        package: opensi_core::Package,
+        selected: Option<PackageNode>,
+    },
 }
 
 impl PackageState {
@@ -128,7 +137,7 @@ impl PackageState {
             Self::Loading(receiver) => {
                 match receiver.try_recv() {
                     Ok(Ok(package)) => {
-                        *self = Self::Active(package);
+                        *self = Self::Active { package, selected: None };
                     },
                     Ok(Err(_err)) => {
                         // TODO: error handle
diff --git a/crates/opensi-editor/src/lib.rs b/crates/opensi-editor/src/lib.rs
index 6a34c75..48f520b 100644
--- a/crates/opensi-editor/src/lib.rs
+++ b/crates/opensi-editor/src/lib.rs
@@ -2,6 +2,12 @@
 
 mod app;
 mod file_dialogs;
+mod package_tab;
 mod package_tree;
+mod question_tab;
+mod round_tab;
+mod theme_tab;
+mod utils;
+mod workarea;
 
 pub use app::EditorApp;
diff --git a/crates/opensi-editor/src/package_tab.rs b/crates/opensi-editor/src/package_tab.rs
new file mode 100644
index 0000000..6c8ad4e
--- /dev/null
+++ b/crates/opensi-editor/src/package_tab.rs
@@ -0,0 +1,8 @@
+use opensi_core::Package;
+
+pub fn package_tab(package: &mut Package, ui: &mut egui::Ui) {
+    ui.vertical(|ui| {
+        ui.label(&package.id);
+        ui.label(package.name.clone().unwrap_or_default());
+    });
+}
diff --git a/crates/opensi-editor/src/package_tree.rs b/crates/opensi-editor/src/package_tree.rs
index edae074..92dedd3 100644
--- a/crates/opensi-editor/src/package_tree.rs
+++ b/crates/opensi-editor/src/package_tree.rs
@@ -1,28 +1,34 @@
-use std::borrow::Cow;
-
 use egui::collapsing_header::CollapsingState;
 use opensi_core::{Package, PackageNode};
 
+use crate::utils::node_name;
+
 /// Ui for a whole [`Package`] in a form of a tree.
 ///
 /// It can add new rounds, themes and questions, edit
 /// names/prices of existing ones and select them.
-pub fn package_tree(package: &mut Package, ui: &mut egui::Ui) {
+pub fn package_tree(package: &mut Package, selected: &mut Option<PackageNode>, ui: &mut egui::Ui) {
     let name = package.name.as_ref().map(|name| name.as_str()).unwrap_or("Новый пакет вопросов");
 
     ui.vertical_centered_justified(|ui| {
-        ui.heading(name);
+        let text = egui::RichText::new(name).strong().heading();
+        if ui.add(egui::Label::new(text).sense(egui::Sense::click()).selectable(false)).clicked() {
+            *selected = None;
+        }
     });
 
     ui.separator();
 
-    egui::ScrollArea::vertical().show(ui, |ui| {
-        tree_node_ui(package, None, ui);
-    });
+    egui::ScrollArea::vertical().show(ui, |ui| tree_node_ui(package, None, selected, ui));
 }
 
 /// Recursive [`PackageNode`] ui.
-fn tree_node_ui<'a>(package: &mut Package, node: Option<PackageNode>, ui: &mut egui::Ui) {
+fn tree_node_ui<'a>(
+    package: &mut Package,
+    node: Option<PackageNode>,
+    selected: &mut Option<PackageNode>,
+    ui: &mut egui::Ui,
+) {
     fn plus_button(ui: &mut egui::Ui) -> bool {
         ui.vertical_centered_justified(|ui| ui.button("➕").clicked()).inner
     }
@@ -145,7 +151,7 @@ fn tree_node_ui<'a>(package: &mut Package, node: Option<PackageNode>, ui: &mut e
                 ui.weak("Нет раундов");
             } else {
                 for index in 0..package.rounds.rounds.len() {
-                    tree_node_ui(package, Some(PackageNode::Round { index }), ui);
+                    tree_node_ui(package, Some(PackageNode::Round { index }), selected, ui);
                 }
             }
         });
@@ -157,11 +163,11 @@ fn tree_node_ui<'a>(package: &mut Package, node: Option<PackageNode>, ui: &mut e
 
     let id = egui::Id::new(node.index()).with(ui.id());
     match node {
-        node @ PackageNode::Round { index } => {
+        PackageNode::Round { index } => {
             CollapsingState::load_with_default_open(ui.ctx(), id, true)
                 .show_header(ui, |ui| {
                     if node_button(package, node, ui) {
-                        // TODO: selected round
+                        *selected = Some(node);
                     };
                 })
                 .body(|ui| {
@@ -173,6 +179,7 @@ fn tree_node_ui<'a>(package: &mut Package, node: Option<PackageNode>, ui: &mut e
                         tree_node_ui(
                             package,
                             Some(PackageNode::Theme { round_index: index, index: theme_index }),
+                            selected,
                             ui,
                         );
                     }
@@ -181,11 +188,11 @@ fn tree_node_ui<'a>(package: &mut Package, node: Option<PackageNode>, ui: &mut e
                     }
                 });
         },
-        node @ PackageNode::Theme { round_index, index } => {
+        PackageNode::Theme { round_index, index } => {
             CollapsingState::load_with_default_open(ui.ctx(), id, false)
                 .show_header(ui, |ui| {
                     if node_button(package, node, ui) {
-                        // TODO: selected theme
+                        *selected = Some(node);
                     };
                 })
                 .body(|ui| {
@@ -201,6 +208,7 @@ fn tree_node_ui<'a>(package: &mut Package, node: Option<PackageNode>, ui: &mut e
                                 theme_index: index,
                                 index: question_index,
                             }),
+                            selected,
                             ui,
                         );
                     }
@@ -211,28 +219,8 @@ fn tree_node_ui<'a>(package: &mut Package, node: Option<PackageNode>, ui: &mut e
         },
         PackageNode::Question { round_index, theme_index, index } => {
             if node_button(package, PackageNode::Question { round_index, theme_index, index }, ui) {
-                // TODO: selected question
+                *selected = Some(node);
             }
         },
     }
 }
-
-/// Utility method to get a button name for a [`PackageNode`].
-fn node_name<'a>(node: PackageNode, package: &'a Package) -> Cow<'a, str> {
-    match node {
-        PackageNode::Round { index } => package
-            .get_round(index)
-            .map(|round| round.name.as_str())
-            .unwrap_or("<Неизвестный раунд>")
-            .into(),
-        PackageNode::Theme { round_index, index } => package
-            .get_theme(round_index, index)
-            .map(|theme| theme.name.as_str())
-            .unwrap_or("<Неизвестная тема>")
-            .into(),
-        PackageNode::Question { round_index, theme_index, index } => package
-            .get_question(round_index, theme_index, index)
-            .map(|question| format!("🗛 ({})", question.price).into())
-            .unwrap_or("<Неизвестный вопрос>".into()),
-    }
-}
diff --git a/crates/opensi-editor/src/question_tab.rs b/crates/opensi-editor/src/question_tab.rs
new file mode 100644
index 0000000..cfb527b
--- /dev/null
+++ b/crates/opensi-editor/src/question_tab.rs
@@ -0,0 +1,7 @@
+use opensi_core::Question;
+
+use crate::utils::todo_label;
+
+pub fn question_tab(_question: &mut Question, ui: &mut egui::Ui) {
+    todo_label(ui);
+}
diff --git a/crates/opensi-editor/src/round_tab.rs b/crates/opensi-editor/src/round_tab.rs
new file mode 100644
index 0000000..012a8bc
--- /dev/null
+++ b/crates/opensi-editor/src/round_tab.rs
@@ -0,0 +1,7 @@
+use opensi_core::Round;
+
+use crate::utils::todo_label;
+
+pub fn round_tab(_round: &mut Round, ui: &mut egui::Ui) {
+    todo_label(ui);
+}
diff --git a/crates/opensi-editor/src/theme_tab.rs b/crates/opensi-editor/src/theme_tab.rs
new file mode 100644
index 0000000..8074a12
--- /dev/null
+++ b/crates/opensi-editor/src/theme_tab.rs
@@ -0,0 +1,7 @@
+use opensi_core::Theme;
+
+use crate::utils::todo_label;
+
+pub fn theme_tab(_theme: &mut Theme, ui: &mut egui::Ui) {
+    todo_label(ui);
+}
diff --git a/crates/opensi-editor/src/utils.rs b/crates/opensi-editor/src/utils.rs
new file mode 100644
index 0000000..b171456
--- /dev/null
+++ b/crates/opensi-editor/src/utils.rs
@@ -0,0 +1,36 @@
+use std::{borrow::Cow, fmt::Display};
+
+use opensi_core::{Package, PackageNode};
+
+/// A generic error label.
+pub fn error_label(error: impl Display, ui: &mut egui::Ui) {
+    let text = egui::RichText::new(error.to_string()).color(egui::Color32::RED).size(24.0);
+    ui.add(egui::Label::new(text).selectable(true).wrap());
+}
+
+/// A stub todo label.
+pub fn todo_label(ui: &mut egui::Ui) {
+    let text =
+        egui::RichText::new("TODO").background_color(egui::Color32::YELLOW).strong().size(24.0);
+    ui.add(egui::Label::new(text).selectable(false).extend());
+}
+
+/// Utility method to get a button name for a [`PackageNode`].
+pub fn node_name<'a>(node: PackageNode, package: &'a Package) -> Cow<'a, str> {
+    match node {
+        PackageNode::Round { index } => package
+            .get_round(index)
+            .map(|round| round.name.as_str())
+            .unwrap_or("<Неизвестный раунд>")
+            .into(),
+        PackageNode::Theme { round_index, index } => package
+            .get_theme(round_index, index)
+            .map(|theme| theme.name.as_str())
+            .unwrap_or("<Неизвестная тема>")
+            .into(),
+        PackageNode::Question { round_index, theme_index, index } => package
+            .get_question(round_index, theme_index, index)
+            .map(|question| format!("🗛 ({})", question.price).into())
+            .unwrap_or("<Неизвестный вопрос>".into()),
+    }
+}
diff --git a/crates/opensi-editor/src/workarea.rs b/crates/opensi-editor/src/workarea.rs
new file mode 100644
index 0000000..fc72d29
--- /dev/null
+++ b/crates/opensi-editor/src/workarea.rs
@@ -0,0 +1,123 @@
+use crate::{
+    package_tab, question_tab, round_tab, theme_tab,
+    utils::{error_label, node_name},
+};
+use opensi_core::{Package, PackageNode};
+
+/// UI for general area of [`Package`] editing.
+pub fn workarea(package: &mut Package, selected: &mut Option<PackageNode>, ui: &mut egui::Ui) {
+    ui.vertical(|ui| {
+        breadcrumbs(package, selected, ui);
+
+        ui.add_space(16.0);
+
+        ui.centered_and_justified(|ui| {
+            selected_tab(package, selected, ui);
+        });
+    });
+}
+
+/// Tab ui based on what package node is selected.
+fn selected_tab(package: &mut Package, selected: &mut Option<PackageNode>, ui: &mut egui::Ui) {
+    match selected {
+        &mut Some(PackageNode::Round { index }) => {
+            if let Some(round) = package.get_round_mut(index) {
+                round_tab::round_tab(round, ui);
+            } else {
+                let error = format!("Невозможно найти раунд с индексом {index}");
+                error_label(error, ui);
+            }
+        },
+        &mut Some(PackageNode::Theme { round_index, index }) => {
+            if let Some(theme) = package.get_theme_mut(round_index, index) {
+                theme_tab::theme_tab(theme, ui);
+            } else {
+                let error = format!(
+                    "Невозможно найти тему с индексом {index} (раунд с индексом {round_index})"
+                );
+                error_label(error, ui);
+            }
+        },
+        &mut Some(PackageNode::Question { round_index, theme_index, index }) => {
+            if let Some(question) = package.get_question_mut(round_index, theme_index, index) {
+                question_tab::question_tab(question, ui);
+            } else {
+                let error = [
+                    format!("Невозможно найти вопрос с индексом {index}"),
+                    format!("(раунд с индексом {round_index}, тема с индексом {theme_index})"),
+                ]
+                .join(" ");
+                error_label(error, ui);
+            }
+        },
+        None => {
+            package_tab::package_tab(package, ui);
+        },
+    }
+}
+
+/// Selection breadcrumbs ui.
+fn breadcrumbs(package: &Package, selected: &mut Option<PackageNode>, ui: &mut egui::Ui) {
+    fn breadcrumb(text: impl AsRef<str>, ui: &mut egui::Ui) -> bool {
+        let text = egui::RichText::new(text.as_ref()).size(20.0);
+        let response =
+            ui.add(egui::Label::new(text).extend().sense(egui::Sense::click()).selectable(false));
+        response.clicked()
+    }
+
+    fn breadcrump_separator(ui: &mut egui::Ui) {
+        ui.add_space(8.0);
+        let text = egui::RichText::new("/").size(8.0).weak();
+        ui.add(egui::Label::new(text).wrap().selectable(false));
+        ui.add_space(8.0);
+    }
+
+    fn root_breadcrumb(selected: &mut Option<PackageNode>, ui: &mut egui::Ui) {
+        if breadcrumb("🏠", ui) {
+            *selected = None;
+        }
+    }
+
+    fn node_breadcrumb(
+        node: PackageNode,
+        package: &Package,
+        selected: &mut Option<PackageNode>,
+        ui: &mut egui::Ui,
+    ) {
+        let name = node_name(node, package);
+        if breadcrumb(name, ui) {
+            *selected = Some(node);
+        }
+    }
+
+    ui.horizontal(|ui| {
+        root_breadcrumb(selected, ui);
+
+        match *selected {
+            Some(node @ PackageNode::Round { .. }) => {
+                breadcrump_separator(ui);
+                node_breadcrumb(node, package, selected, ui);
+            },
+            Some(node @ PackageNode::Theme { .. }) => {
+                breadcrump_separator(ui);
+                node_breadcrumb(node.get_parent().unwrap(), package, selected, ui);
+                breadcrump_separator(ui);
+                node_breadcrumb(node, package, selected, ui);
+            },
+            Some(node @ PackageNode::Question { .. }) => {
+                breadcrump_separator(ui);
+                node_breadcrumb(
+                    node.get_parent().unwrap().get_parent().unwrap(),
+                    package,
+                    selected,
+                    ui,
+                );
+                breadcrump_separator(ui);
+                node_breadcrumb(node.get_parent().unwrap(), package, selected, ui);
+                breadcrump_separator(ui);
+                node_breadcrumb(node, package, selected, ui);
+            },
+            None => {},
+        }
+    });
+}