diff --git a/cbporganizer-backend/src/main/java/cbporganizer/FileController.java b/cbporganizer-backend/src/main/java/cbporganizer/FileController.java
index e864f5f..65e6c86 100644
--- a/cbporganizer-backend/src/main/java/cbporganizer/FileController.java
+++ b/cbporganizer-backend/src/main/java/cbporganizer/FileController.java
@@ -2,11 +2,14 @@
 
 import cbporganizer.service.FilesStorageService;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
+import org.springframework.web.client.HttpClientErrorException;
 import org.springframework.web.multipart.MultipartFile;
 
+import javax.servlet.http.HttpSession;
 import java.util.List;
 
 @RestController
@@ -17,14 +20,26 @@ public class FileController {
     FilesStorageService storageService;
 
     @PostMapping("/upload")
-    public ResponseEntity<String> uploadFile(@RequestParam("file") MultipartFile file) {
-        storageService.save(file);
+    public ResponseEntity<String> uploadFile(@RequestParam("file") MultipartFile file, HttpSession session) {
+        String userId = getUserIdFromSession(session);
+
+        storageService.save(file, userId);
         return ResponseEntity.status(HttpStatus.OK).body("Uploaded the file successfully: " + file.getOriginalFilename());
     }
 
     @GetMapping("/")
-    public ResponseEntity<List<String>> getFiles() {
-        List<String> fileList = storageService.getFiles();
+    public ResponseEntity<List<String>> getFiles(HttpSession session) {
+        String userId = getUserIdFromSession(session);
+
+        List<String> fileList = storageService.getFiles(userId);
         return new ResponseEntity<>(fileList, HttpStatus.OK);
     }
+
+    private String getUserIdFromSession(HttpSession session) {
+        String userId = (String) session.getAttribute("userId");
+        if (userId == null) {
+            throw HttpClientErrorException.Unauthorized.create(HttpStatus.UNAUTHORIZED, "Unauthorized", HttpHeaders.EMPTY, null, null);
+        }
+        return userId;
+    }
 }
diff --git a/cbporganizer-backend/src/main/java/cbporganizer/service/FilesStorageService.java b/cbporganizer-backend/src/main/java/cbporganizer/service/FilesStorageService.java
index e14eff0..7c2e6a8 100644
--- a/cbporganizer-backend/src/main/java/cbporganizer/service/FilesStorageService.java
+++ b/cbporganizer-backend/src/main/java/cbporganizer/service/FilesStorageService.java
@@ -8,7 +8,7 @@ public interface FilesStorageService {
 
     void init();
 
-    void save(MultipartFile file);
+    void save(MultipartFile file, String userId);
 
-    List<String> getFiles();
+    List<String> getFiles(String userId);
 }
diff --git a/cbporganizer-backend/src/main/java/cbporganizer/service/FilesStorageServiceImpl.java b/cbporganizer-backend/src/main/java/cbporganizer/service/FilesStorageServiceImpl.java
index 965410b..f37c247 100644
--- a/cbporganizer-backend/src/main/java/cbporganizer/service/FilesStorageServiceImpl.java
+++ b/cbporganizer-backend/src/main/java/cbporganizer/service/FilesStorageServiceImpl.java
@@ -30,28 +30,41 @@ public void init() {
     }
 
     @Override
-    public void save(MultipartFile file) {
-        Path filePath = this.root.resolve(file.getOriginalFilename());
+    public void save(MultipartFile file, String userId) {
+        Path userDir = getUserPath(userId);
         try {
+            if (!Files.exists(userDir)) {
+                Files.createDirectory(userDir);
+            }
+            Path filePath = userDir.resolve(file.getOriginalFilename());
+
             Files.copy(file.getInputStream(), filePath, java.nio.file.StandardCopyOption.REPLACE_EXISTING);
 
-            extractGZip(filePath.toFile());
+            extractGZip(filePath.toFile(), userId);
         } catch (IOException e) {
             e.printStackTrace();
         }
     }
 
-    private void extractGZip(File inputFile) {
+    /*
+     * Resolves the path to the user's directory by the userId.
+     */
+    private Path getUserPath(String userId) {
+        return root.resolve(userId);
+    }
+
+    private void extractGZip(File inputFile, String userId) {
+        Path userDir = getUserPath(userId);
         try {
             TarArchiveInputStream tarInput = new TarArchiveInputStream(new GZIPInputStream(new FileInputStream(inputFile)));
 
             TarArchiveEntry entry;
             while((entry = tarInput.getNextTarEntry()) != null) {
                 if (entry.isDirectory()) {
-                    new File(root.resolve(entry.getName()).toString()).mkdirs();
+                    new File(userDir.resolve(entry.getName()).toString()).mkdirs();
                 } else {
                     byte[] buffer = new byte[1024];
-                    File outFile = root.resolve(entry.getName()).toFile();
+                    File outFile = userDir.resolve(entry.getName()).toFile();
                     outFile.getParentFile().mkdirs();
                     try (FileOutputStream fos = new FileOutputStream(outFile)) {
                         int len;
@@ -67,10 +80,11 @@ private void extractGZip(File inputFile) {
     }
 
     @Override
-    public List<String> getFiles() {
+    public List<String> getFiles(String userId) {
+        Path userDir = getUserPath(userId);
         List<String> ret = new LinkedList<>();
         try {
-            ret = Files.walk(root)
+            ret = Files.walk(userDir)
                     .filter(Files::isRegularFile)
                     .map(file -> file.getFileName().toString())
                     .collect(Collectors.toList());