diff --git a/frontend/src/app/shared/service/auth.service.ts b/frontend/src/app/shared/service/auth.service.ts
index f73183c..4763c8b 100644
--- a/frontend/src/app/shared/service/auth.service.ts
+++ b/frontend/src/app/shared/service/auth.service.ts
@@ -1,38 +1,77 @@
-import { HttpClient } from '@angular/common/http';
+import { HttpClient, HttpHeaders } from '@angular/common/http';
 import { Injectable } from '@angular/core';
-import { Router } from '@angular/router';
+
+import { BehaviorSubject } from 'rxjs';
 
 import { environment } from '../../../environments/environment';
 import { LoginCredentials, Tokens } from '../types';
 
+import { LocalStorageService } from './local-storage.service';
+import { SessionStorageService } from './session-storage.service';
+
 @Injectable({
   providedIn: 'root',
 })
 export class AuthService {
-  private isAuthenticated: boolean = false;
+  private readonly path: string = '/api/auth';
   private access_token: string | null = null;
   private refresh_token: string | null = null;
+  private isAuthenticated$: BehaviorSubject<boolean> =
+    new BehaviorSubject<boolean>(false);
 
   public constructor(
     private readonly httpClient: HttpClient,
-    private readonly router: Router
+    private readonly localStorageService: LocalStorageService,
+    private readonly sessionStorageService: SessionStorageService
   ) {}
 
   public signin(credentials: LoginCredentials): void {
     this.httpClient
-      .post<Tokens>(environment.api.base + '/api/auth/signin', credentials)
+      .post<Tokens>(environment.api.base + `${this.path}/signin`, credentials)
       .subscribe((response: Tokens) => {
-        this.access_token = response.access_token;
-        this.refresh_token = response.refresh_token;
+        this.handleSuccess(response);
       });
   }
 
   public signup(credentials: LoginCredentials): void {
     this.httpClient
-      .post<Tokens>(environment.api.base + '/api/auth/signup', credentials)
+      .post<Tokens>(environment.api.base + `${this.path}/signup`, credentials)
       .subscribe((response: Tokens) => {
-        this.access_token = response.access_token;
-        this.refresh_token = response.refresh_token;
+        // The checked accept terms should be saved with a timestamp in the db
+        this.handleSuccess(response);
       });
   }
+
+  public signout(): void {
+    this.access_token = null;
+    this.refresh_token = null;
+    this.localStorageService.removeItem('access_token');
+    this.sessionStorageService.removeItem('refresh_token');
+    this.isAuthenticated$.next(false);
+  }
+
+  public refreshToken(): void {
+    const headers = new HttpHeaders().set(
+      'Authorization',
+      'Bearer ' + this.refresh_token
+    );
+
+    this.httpClient
+      .post<Tokens>(
+        environment.api.base + `${this.path}/refresh`,
+        {},
+        { headers: headers }
+      )
+      .subscribe((response: Tokens) => {
+        this.handleSuccess(response);
+      });
+  }
+
+  private handleSuccess(tokens: Tokens): void {
+    this.access_token = tokens.access_token;
+    this.refresh_token = tokens.refresh_token;
+    this.localStorageService.setItem('access_token', tokens.access_token);
+    this.sessionStorageService.setItem('refresh_token', tokens.refresh_token);
+    this.isAuthenticated$.next(true);
+  }
 }
diff --git a/frontend/src/app/shared/service/base-storage.service.ts b/frontend/src/app/shared/service/base-storage.service.ts
new file mode 100644
index 0000000..24dcb19
--- /dev/null
+++ b/frontend/src/app/shared/service/base-storage.service.ts
@@ -0,0 +1,33 @@
+import { EncryptionService } from './encryption.service';
+import { SanitizationService } from './sanitization.service';
+
+export abstract class BaseStorageService {
+  protected abstract getStorage(): Storage;
+
+  public setItem<T>(key: string, value: T): void {
+    const sanitizedValue = SanitizationService.sanitize(JSON.stringify(value));
+    const encryptedValue = EncryptionService.encrypt(sanitizedValue);
+
+    this.getStorage().setItem(key, encryptedValue);
+  }
+
+  public getItem<T>(key: string): T | null {
+    const encryptedValue = this.getStorage().getItem(key);
+
+    if (encryptedValue) {
+      const decryptedValue = EncryptionService.decrypt(encryptedValue);
+      const sanitizedValue = SanitizationService.sanitize(decryptedValue);
+
+      return JSON.parse(sanitizedValue) as T;
+    }
+    return null;
+  }
+
+  public removeItem(key: string): void {
+    this.getStorage().removeItem(key);
+  }
+
+  public clear(): void {
+    this.getStorage().clear();
+  }
+}
diff --git a/frontend/src/app/shared/service/encryption.service.ts b/frontend/src/app/shared/service/encryption.service.ts
new file mode 100644
index 0000000..8823749
--- /dev/null
+++ b/frontend/src/app/shared/service/encryption.service.ts
@@ -0,0 +1,15 @@
+import * as CryptoJS from 'crypto-js';
+
+import { environment } from '../../../environments/environment';
+
+export class EncryptionService {
+  private static readonly key: string = environment.security.encryptionKey;
+
+  public static encrypt(data: string): string {
+    return CryptoJS.AES.encrypt(data, this.key).toString();
+  }
+
+  public static decrypt(data: string): string {
+    return CryptoJS.AES.decrypt(data, this.key).toString(CryptoJS.enc.Utf8);
+  }
+}
diff --git a/frontend/src/app/shared/service/index.ts b/frontend/src/app/shared/service/index.ts
index 2a719d1..f11d653 100644
--- a/frontend/src/app/shared/service/index.ts
+++ b/frontend/src/app/shared/service/index.ts
@@ -1 +1,3 @@
 export * from './auth.service';
+export * from './local-storage.service';
+export * from './session-storage.service';
diff --git a/frontend/src/app/shared/service/local-storage.service.ts b/frontend/src/app/shared/service/local-storage.service.ts
new file mode 100644
index 0000000..34fd729
--- /dev/null
+++ b/frontend/src/app/shared/service/local-storage.service.ts
@@ -0,0 +1,12 @@
+import { Injectable } from '@angular/core';
+
+import { BaseStorageService } from './base-storage.service';
+
+@Injectable({
+  providedIn: 'root',
+})
+export class LocalStorageService extends BaseStorageService {
+  protected getStorage(): Storage {
+    return localStorage;
+  }
+}
diff --git a/frontend/src/app/shared/service/sanitization.service.ts b/frontend/src/app/shared/service/sanitization.service.ts
new file mode 100644
index 0000000..a787262
--- /dev/null
+++ b/frontend/src/app/shared/service/sanitization.service.ts
@@ -0,0 +1,7 @@
+import DOMPurify from 'dompurify';
+
+export class SanitizationService {
+  public static sanitize(data: string): string {
+    return DOMPurify.sanitize(data);
+  }
+}
diff --git a/frontend/src/app/shared/service/session-storage.service.ts b/frontend/src/app/shared/service/session-storage.service.ts
new file mode 100644
index 0000000..c31601b
--- /dev/null
+++ b/frontend/src/app/shared/service/session-storage.service.ts
@@ -0,0 +1,12 @@
+import { Injectable } from '@angular/core';
+
+import { BaseStorageService } from './base-storage.service';
+
+@Injectable({
+  providedIn: 'root',
+})
+export class SessionStorageService extends BaseStorageService {
+  protected getStorage(): Storage {
+    return sessionStorage;
+  }
+}