diff --git a/GBase/FileHandling/FileHandler.cs b/GBase/FileHandling/FileHandler.cs
index 4e1d396..58162dc 100644
--- a/GBase/FileHandling/FileHandler.cs
+++ b/GBase/FileHandling/FileHandler.cs
@@ -38,12 +38,26 @@ namespace GBase.FileHandling
         /// Initialize this <see cref="IFileHandler"/>
         /// </summary>
         /// <param name="path">The path of the database</param>
+        /// <param name="folderName"></param>
         /// <param name="cancellationToken">A <see cref="CancellationToken"/> to cancel the asynchronous operation</param>
         /// <returns>True if successful, false if not</returns>
-        public async Task<bool> Init(string path, CancellationToken cancellationToken)
+        public List<IGBaseFile> Init(string path, string folderName, CancellationToken cancellationToken)
         {
             _path = path;
-            return true; //TODO: initialize existing files
+            
+            string directoryPath = Path.Combine(_path, folderName);
+            if (!Directory.Exists(directoryPath))
+                return null;
+            
+            string[] files = Directory.GetFiles(directoryPath, $"*.{GBASE_TABLE_FILE_EXTENSION}");
+
+            foreach (var file in files)
+            {
+                FileStream entryFile = File.Open(file, FileMode.OpenOrCreate, FileAccess.ReadWrite);
+                _files.Add(new GBaseFile(null, entryFile, file));
+            }
+            
+            return _files;
         }
 
         public IGBaseFile CreateEntryFile<T>(T entry, IGBaseTable table)
@@ -55,9 +69,14 @@ namespace GBase.FileHandling
             
             //create new entry file
             string filePath = $"{Path.Combine(directoryPath, entry.ToString())}.{GBASE_TABLE_FILE_EXTENSION}";
-            FileStream entryFile = File.Open(filePath, FileMode.OpenOrCreate, FileAccess.ReadWrite); //TODO: Stream has to be disposed
+
+            //check if file is already opened
+            IGBaseFile file = _files.FirstOrDefault(f => f.FilePath.Equals(filePath));
+            if (file != null) 
+                return file.UseFile();
             
-            IGBaseFile file = new GBaseFile(entry, entryFile, filePath);
+            FileStream entryFile = File.Open(filePath, FileMode.OpenOrCreate, FileAccess.ReadWrite);
+            file = new GBaseFile(entry, entryFile, filePath);
             _files.Add(file);
 
             return file.UseFile();
diff --git a/GBase/Interfaces/FileHandling/IFileHandler.cs b/GBase/Interfaces/FileHandling/IFileHandler.cs
index 0e9ca47..e0f9497 100644
--- a/GBase/Interfaces/FileHandling/IFileHandler.cs
+++ b/GBase/Interfaces/FileHandling/IFileHandler.cs
@@ -3,6 +3,7 @@
 // Copyright(c) 2020 SimonG. All Rights Reserved.
 
 using System;
+using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -17,9 +18,10 @@ namespace GBase.Interfaces.FileHandling
         /// Initialize this <see cref="IFileHandler"/>
         /// </summary>
         /// <param name="path">The path of the database</param>
+        /// <param name="folderName"></param>
         /// <param name="cancellationToken">A <see cref="CancellationToken"/> to cancel the asynchronous operation</param>
         /// <returns>True if successful, false if not</returns>
-        Task<bool> Init(string path, CancellationToken cancellationToken);
+        List<IGBaseFile> Init(string path, string folderName, CancellationToken cancellationToken);
 
         IGBaseFile CreateEntryFile<T>(T entry, IGBaseTable table);