diff --git a/src/app/MainWindow.cpp b/src/app/MainWindow.cpp
new file mode 100644
index 0000000..4e500f2
--- /dev/null
+++ b/src/app/MainWindow.cpp
@@ -0,0 +1,27 @@
+/**
+ * @file    MainWindow.cpp
+ * @brief   Implementation of the MainWindow class.
+ *
+ * @author  Emilio Soriano Chávez
+ */
+
+#include "MainWindow.hpp"
+
+/**
+ * @brief   Constructs the main window of the application.
+ */
+MainWindow::MainWindow ()
+{
+    /* Window Properties */
+    setWindowTitle("Ensemble");
+    setMinimumSize(850, 400);
+
+    /* Remove margins between widgets. */
+    setContentsMargins(0, 0, 0, 0);
+
+    _layout = new QVBoxLayout {};
+    setLayout(_layout);
+
+    _topbar = new TopBar {};
+    _layout -> addWidget(_topbar);
+}
diff --git a/src/app/MainWindow.hpp b/src/app/MainWindow.hpp
new file mode 100644
index 0000000..6bd6040
--- /dev/null
+++ b/src/app/MainWindow.hpp
@@ -0,0 +1,28 @@
+/**
+ * @file    MainWindow.hpp
+ * @brief   The main window for Ensemble, containing the Top Bar, the Sidebar,
+ *          the Music Player, and the View Manager.
+ *
+ * @author  Emilio Soriano Chávez
+ */
+
+#ifndef MAINWINDOW_HPP
+#define MAINWINDOW_HPP
+
+#include <QWidget>
+#include <QVBoxLayout>
+
+#include "TopBar.hpp"
+
+class MainWindow : public QWidget
+{
+    public:
+        MainWindow ();
+
+    private:
+        QVBoxLayout* _layout = nullptr;
+
+        TopBar* _topbar = nullptr;
+};
+
+#endif