diff --git a/src/RoleEditor/App.config b/src/RoleEditor/App.config
index 49cc43e..7c6ee29 100644
--- a/src/RoleEditor/App.config
+++ b/src/RoleEditor/App.config
@@ -1,3 +1,15 @@
 <?xml version="1.0" encoding="utf-8" ?>
 <configuration>
+    <configSections>
+        <sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
+            <section name="RoleEditor.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
+        </sectionGroup>
+    </configSections>
+    <applicationSettings>
+        <RoleEditor.Properties.Settings>
+            <setting name="ConnectionString" serializeAs="String">
+                <value>Server=localhost;User ID=ds;Password=HalloWach_2323XXL!!;Database=bremen_calling;Port=33306</value>
+            </setting>
+        </RoleEditor.Properties.Settings>
+    </applicationSettings>
 </configuration>
\ No newline at end of file
diff --git a/src/RoleEditor/MainWindow.xaml.cs b/src/RoleEditor/MainWindow.xaml.cs
index 6bc1a6f..c3b4cef 100644
--- a/src/RoleEditor/MainWindow.xaml.cs
+++ b/src/RoleEditor/MainWindow.xaml.cs
@@ -49,11 +49,11 @@ namespace RoleEditor
         }
 
         private async void Window_Loaded(object sender, RoutedEventArgs e)
-        {
-            
-            // try database connection
+        {                       
             try
             {
+                DBManager.SetConnectionString(Properties.Settings.Default.ConnectionString);
+
                 // load all participants
                 List<Participant> participants = await Participant.LoadAll(_dbManager);
                 foreach(Participant p in participants)
diff --git a/src/RoleEditor/Properties/Settings.Designer.cs b/src/RoleEditor/Properties/Settings.Designer.cs
new file mode 100644
index 0000000..eab12af
--- /dev/null
+++ b/src/RoleEditor/Properties/Settings.Designer.cs
@@ -0,0 +1,36 @@
+//------------------------------------------------------------------------------
+// <auto-generated>
+//     This code was generated by a tool.
+//     Runtime Version:4.0.30319.42000
+//
+//     Changes to this file may cause incorrect behavior and will be lost if
+//     the code is regenerated.
+// </auto-generated>
+//------------------------------------------------------------------------------
+
+namespace RoleEditor.Properties {
+    
+    
+    [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]
+    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.Editors.SettingsDesigner.SettingsSingleFileGenerator", "17.5.0.0")]
+    internal sealed partial class Settings : global::System.Configuration.ApplicationSettingsBase {
+        
+        private static Settings defaultInstance = ((Settings)(global::System.Configuration.ApplicationSettingsBase.Synchronized(new Settings())));
+        
+        public static Settings Default {
+            get {
+                return defaultInstance;
+            }
+        }
+        
+        [global::System.Configuration.ApplicationScopedSettingAttribute()]
+        [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
+        [global::System.Configuration.DefaultSettingValueAttribute("Server=localhost;User ID=ds;Password=HalloWach_2323XXL!!;Database=bremen_calling;" +
+            "Port=33306")]
+        public string ConnectionString {
+            get {
+                return ((string)(this["ConnectionString"]));
+            }
+        }
+    }
+}
diff --git a/src/RoleEditor/Properties/Settings.settings b/src/RoleEditor/Properties/Settings.settings
new file mode 100644
index 0000000..497dc89
--- /dev/null
+++ b/src/RoleEditor/Properties/Settings.settings
@@ -0,0 +1,9 @@
+<?xml version='1.0' encoding='utf-8'?>
+<SettingsFile xmlns="http://schemas.microsoft.com/VisualStudio/2004/01/settings" CurrentProfile="(Default)" GeneratedClassNamespace="RoleEditor.Properties" GeneratedClassName="Settings">
+  <Profiles />
+  <Settings>
+    <Setting Name="ConnectionString" Type="System.String" Scope="Application">
+      <Value Profile="(Default)">Server=localhost;User ID=ds;Password=HalloWach_2323XXL!!;Database=bremen_calling;Port=33306</Value>
+    </Setting>
+  </Settings>
+</SettingsFile>
\ No newline at end of file
diff --git a/src/RoleEditor/RoleEditor.csproj b/src/RoleEditor/RoleEditor.csproj
index a158f56..58869d9 100644
--- a/src/RoleEditor/RoleEditor.csproj
+++ b/src/RoleEditor/RoleEditor.csproj
@@ -60,6 +60,11 @@
   </ItemGroup>
 
   <ItemGroup>
+    <Compile Update="Properties\Settings.Designer.cs">
+      <DesignTimeSharedInput>True</DesignTimeSharedInput>
+      <AutoGen>True</AutoGen>
+      <DependentUpon>Settings.settings</DependentUpon>
+    </Compile>
     <Compile Update="Resources.Designer.cs">
       <DesignTime>True</DesignTime>
       <AutoGen>True</AutoGen>
@@ -74,4 +79,11 @@
     </EmbeddedResource>
   </ItemGroup>
 
+  <ItemGroup>
+    <None Update="Properties\Settings.settings">
+      <Generator>SettingsSingleFileGenerator</Generator>
+      <LastGenOutput>Settings.Designer.cs</LastGenOutput>
+    </None>
+  </ItemGroup>
+
 </Project>
diff --git a/src/brecal.mysql/DBManager.cs b/src/brecal.mysql/DBManager.cs
index 9e589a3..d5c5571 100644
--- a/src/brecal.mysql/DBManager.cs
+++ b/src/brecal.mysql/DBManager.cs
@@ -1,15 +1,19 @@
 using brecal.model;
 using MySqlConnector;
 using System.Data;
-using System.Runtime.CompilerServices;
 using static brecal.model.IDBManager;
 
 namespace brecal.mysql
 {
     public class DBManager : IDBManager
     {
-        // TODO: remove this and use external configuration
-        private static readonly string _connectionString = "Server=localhost;User ID=ds;Password=HalloWach_2323XXL!!;Database=bremen_calling;Port=33306";       
+
+        private static string _connectionString = "";
+
+        public static void SetConnectionString(string connectionString)
+        {
+            _connectionString = connectionString;
+        }
 
         public async Task<List<DbEntity>> Load(QueryFunc prepareAction, LoadFunc<IDataReader> loadAction, params object?[] args)
         {