diff --git a/src/main/java/de/hitec/nhplus/login/User.java b/src/main/java/de/hitec/nhplus/login/User.java
new file mode 100644
index 0000000..52ab712
--- /dev/null
+++ b/src/main/java/de/hitec/nhplus/login/User.java
@@ -0,0 +1,34 @@
+package de.hitec.nhplus.login;
+
+import de.hitec.nhplus.nurse.Nurse;
+
+public class User {
+
+    private int id;
+    private String username;
+    private int permissions = 0;
+    private Nurse nurse;
+
+    public User(
+            int id,
+            String username,
+            int permissions,
+            Nurse nurse
+    ) {
+        this.id = id;
+        this.username = username;
+        this.permissions = permissions;
+        this.nurse = nurse;
+    }
+
+    public User(
+            String username,
+            int permissions,
+            Nurse nurse,
+            boolean admin
+    ) {
+        this.username = username;
+        this.permissions = permissions;
+        this.nurse = nurse;
+    }
+}
diff --git a/src/main/java/de/hitec/nhplus/login/database/UserDao.java b/src/main/java/de/hitec/nhplus/login/database/UserDao.java
new file mode 100644
index 0000000..eea6bfb
--- /dev/null
+++ b/src/main/java/de/hitec/nhplus/login/database/UserDao.java
@@ -0,0 +1,90 @@
+package de.hitec.nhplus.login.database;
+
+import de.hitec.nhplus.datastorage.Dao;
+import de.hitec.nhplus.datastorage.DaoFactory;
+import de.hitec.nhplus.login.User;
+import de.hitec.nhplus.nurse.Nurse;
+
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.util.List;
+
+public class UserDao implements Dao<User> {
+
+
+    protected final Connection connection;
+
+    public UserDao(Connection connection) {
+        this.connection = connection;
+    }
+
+    public int readUserId(String username) throws SQLException {
+        final String SQL = "SELECT id FROM user WHERE username = ?";
+        PreparedStatement statement = this.connection.prepareStatement(SQL);
+        statement.setString(1, username);
+        return statement.executeQuery().getInt(1);
+    }
+
+    public byte[] readPasswordSalt(int id) throws SQLException {
+        final String SQL = "SELECT passwordSalt FROM user WHERE id = ?";
+        PreparedStatement statement = this.connection.prepareStatement(SQL);
+        statement.setInt(1, id);
+        return statement.executeQuery().getBytes(1);
+    }
+
+    public byte[] readPasswordHash(int id) throws SQLException {
+        final String SQL = "SELECT passwordHash FROM user WHERE id = ?";
+        PreparedStatement statement = this.connection.prepareStatement(SQL);
+        statement.setInt(1, id);
+        return statement.executeQuery().getBytes(1);
+    }
+
+    // User
+    @Override
+    public User read(int id) throws SQLException {
+        final String SQL = """
+                SELECT user.username, user__permissions.permissions, user__nurse.nurseId
+                FROM user
+                LEFT JOIN user__permissions ON user.id = user__permissions.userId
+                LEFT JOIN user__nurse ON user.id = user__nurse.userId
+                WHERE user.id = ?;
+        """;
+        PreparedStatement statement = this.connection.prepareStatement(SQL);
+        statement.setInt(1, id);
+        ResultSet result = statement.executeQuery();
+        int nurseId = result.getInt(3);
+        Nurse nurse = null;
+        if (!result.wasNull()) {
+            nurse = DaoFactory.getInstance().createNurseDAO().read(nurseId);
+        }
+        return new User(
+                id,
+                result.getString(1),
+                result.getInt(2),
+                nurse
+        );
+    }
+
+    // Administration
+    @Override
+    public void create(User user) throws SQLException {
+
+    }
+
+    @Override
+    public void update(User user) throws SQLException {
+
+    }
+
+    @Override
+    public void delete(int id) throws SQLException {
+
+    }
+
+    @Override
+    public List<User> readAll() throws SQLException {
+        return null;
+    }
+}
diff --git a/src/main/resources/de/hitec/nhplus/login/database/User.sql b/src/main/resources/de/hitec/nhplus/login/database/User.sql
index b92a04a..8773d00 100644
--- a/src/main/resources/de/hitec/nhplus/login/database/User.sql
+++ b/src/main/resources/de/hitec/nhplus/login/database/User.sql
@@ -1,7 +1,7 @@
 CREATE TABLE user
 (
     id INTEGER PRIMARY KEY AUTOINCREMENT,
-    username TEXT NOT NULL,
+    username TEXT NOT NULL UNIQUE,
     passwordSalt BLOB NOT NULL,
     passwordHash BLOB NOT NULL
 )
\ No newline at end of file
diff --git a/src/main/resources/de/hitec/nhplus/login/database/UserPermission.sql b/src/main/resources/de/hitec/nhplus/login/database/UserPermission.sql
index 536dce0..4a266d8 100644
--- a/src/main/resources/de/hitec/nhplus/login/database/UserPermission.sql
+++ b/src/main/resources/de/hitec/nhplus/login/database/UserPermission.sql
@@ -1,6 +1,6 @@
 CREATE TABLE user__permissions
 (
     userId  INTEGER NOT NULL,
-    permissions INTEGER, -- Binary Bitmask for Permissions
+    permissions INTEGER NOT NULL, -- Binary Bitmask for Permissions
     FOREIGN KEY (userId) REFERENCES user (id) ON DELETE CASCADE
 )
\ No newline at end of file