diff --git a/CsvBuilder.cs b/CsvBuilder.cs
new file mode 100644
index 0000000..ddfc149
--- /dev/null
+++ b/CsvBuilder.cs
@@ -0,0 +1,60 @@
+using System.Collections.Generic;
+using System.Text;
+
+namespace Logof_Client;
+
+public class CsvBuilder
+{
+    private readonly string Header;
+    private readonly List<object> Instances;
+    private readonly KasAddressList KasAddressList;
+
+    public CsvBuilder(string header, List<object> instances)
+    {
+        Header = header;
+        Instances = instances;
+    }
+
+    public CsvBuilder(string header, KasAddressList instances)
+    {
+        Header = header;
+        KasAddressList = instances;
+    }
+
+    public string? BuildKas()
+    {
+        var result = new StringBuilder();
+
+        result.AppendLine(Header);
+        foreach (var l in KasAddressList.KasPersons)
+
+            result.AppendLine(
+                l.refsid + "," +
+                l.anrede + "," +
+                l.titel + "," +
+                l.vorname + "," +
+                l.adel + "," +
+                l.name + "," +
+                l.namezus + "," +
+                l.anredzus + "," +
+                l.strasse + "," +
+                l.strasse2 + "," +
+                l.plz + "," +
+                l.ort + "," +
+                l.land + "," +
+                l.pplz + "," +
+                l.postfach + "," +
+                l.name1 + "," +
+                l.name2 + "," +
+                l.name3 + "," +
+                l.name4 + "," +
+                l.name5 + "," +
+                l.funktion + "," +
+                l.funktion2 + "," +
+                l.abteilung + "," +
+                l.funktionad);
+
+        // weitere Cases
+        return result.ToString();
+    }
+}
\ No newline at end of file