diff --git a/src/login/authInterceptor.ts b/src/login/authInterceptor.ts
index 7dce326..bd3c984 100644
--- a/src/login/authInterceptor.ts
+++ b/src/login/authInterceptor.ts
@@ -1,48 +1,91 @@
 // vim: set tw=80 ts=2 sw=2 sts=2 :
 
-import { Injectable } from '@angular/core';
+import { Injectable, Injector } from '@angular/core';
 import {
   HttpEvent, HttpInterceptor, HttpHandler, HttpRequest, HttpErrorResponse
 } from '@angular/common/http';
 
 import { Observable} from 'rxjs/Rx';
-import 'rxjs/add/operator/map';
+import 'rxjs/add/operator/catch';
 
 import { Logger } from '@nsalaun/ng-logger';
 
 import { LoginService } from './login.service';
+import { Token } from './token';
 
 @Injectable()
 export class AuthInterceptor implements HttpInterceptor {
+  private observable: Observable<Token>;
+
   constructor(
     private logger: Logger,
-    private loginService: LoginService,
+    private injector: Injector,
   ) {}
 
+  injectAuthorizationHeader(request: HttpRequest<any>, accessToken: string) {
+    this.logger.log('Injecting Authorization header');
+
+    return request;
+  }
+
   intercept(
-    req: HttpRequest<any>,
-    next: HttpHandler
+    request: HttpRequest<any>,
+    next: HttpHandler,
+    pass?: number
   ): Observable<HttpEvent<any>> {
-    this.logger.log('Intercepted request', req, next);
-
-    if(!req.headers.has('Authorization')) {
-      let accessToken: string = this.loginService.accessToken();
-
-      if(accessToken){
-        req = req.clone({
-          headers: req.headers.set('Authorization', `Bearer ${accessToken}`)
-        });
-      }
+    if(!pass) {
+      pass = 1;
     }
 
-    this.logger.log('Request', req);
+    let loginService = this.injector.get(LoginService);
 
-    return next.handle(req).map(
-      (event: HttpEvent<any>) => event,
-      (error) => {
-        if(error instanceof HttpErrorResponse && error.status === 401) {
-          this.logger.error('Unauthorized', error);
+    if(request.url == loginService.url) {
+      this.logger.log("Login URL, do not handle.");
+
+      return next.handle(request);
+    }
+
+    this.logger.log(`Intercepted request, pass #${pass}`, request, next);
+
+    let accessToken = loginService.accessToken;
+
+    if(accessToken){
+      request = request.clone({
+        headers: request.headers.set('Authorization', `Bearer ${accessToken}`)
+      });
+    }
+
+    this.logger.log('Request', request);
+
+    let observable: Observable<any> = next.handle(request);
+
+    return observable.catch(
+      (error, caught): Observable<any> => {
+        this.logger.error("Error", error, caught);
+
+        if(!(error instanceof HttpErrorResponse) || error.status != 401) {
+          return Observable.throw(error);
         }
+
+        this.logger.log('Unauthorized', error);
+
+        if(pass === 3) {
+          return Observable.throw(error);
+        }
+
+        if(!this.observable) {
+          this.logger.log("No current login observable.")
+          this.observable = loginService.login();
+        }
+
+        return this.observable.flatMap((token: Token): Observable<HttpEvent<any>> => {
+          this.logger.log("Logged in, access_token:", token.access_token);
+          this.observable = null;
+          return this.intercept(request, next, ++pass);
+        }).catch((error) => {
+          this.observable = null;
+          return Observable.throw(error);
+        });
       }
     );
   }
diff --git a/src/login/login.module.ts b/src/login/login.module.ts
index d84e07c..cb1a735 100644
--- a/src/login/login.module.ts
+++ b/src/login/login.module.ts
@@ -1,15 +1,21 @@
 // vim: set tw=80 ts=2 sw=2 sts=2 :
 
 import { NgModule } from '@angular/core';
+import { FormsModule } from '@angular/forms';
+import { HttpClientModule } from '@angular/common/http';
 import { HTTP_INTERCEPTORS } from '@angular/common/http';
 
 import { NgLoggerModule } from '@nsalaun/ng-logger';
 
-import { LoginService } from './login.service';
 import { AuthInterceptor } from './authInterceptor';
+import { LoginService } from './login.service';
+import { LoginForm } from './loginForm.component';
+import { LoginModalComponent } from './loginModal.component';
 
 @NgModule({
   imports: [
+    HttpClientModule,
+    FormsModule,
     NgLoggerModule,
   ],
   providers: [
@@ -19,6 +25,14 @@ import { AuthInterceptor } from './authInterceptor';
       useClass: AuthInterceptor,
       multi: true
     }
+  ],
+  declarations: [
+    LoginModalComponent,
+    LoginForm,
+  ],
+  entryComponents: [
+    LoginModalComponent,
+    LoginForm,
   ]
 })
 export class LoginModule {};
diff --git a/src/login/login.service.ts b/src/login/login.service.ts
index 14e6994..7418807 100644
--- a/src/login/login.service.ts
+++ b/src/login/login.service.ts
@@ -1,10 +1,67 @@
 import { Injectable } from '@angular/core';
+import { HttpClient, HttpHeaders } from '@angular/common/http';
+
+import { Observable} from 'rxjs/Rx';
 
 import * as base64 from 'base64util';
 
+import { Logger } from '@nsalaun/ng-logger';
+import { NgbModal } from '@ng-bootstrap/ng-bootstrap';
+
+import { Token } from './token';
+import { LoginModalComponent } from './loginModal.component';
+import { Login } from './login';
+
 @Injectable()
 export class LoginService {
-    accessToken() {
+
+    constructor(
+        private httpClient: HttpClient,
+        private logger: Logger,
+        private ngbModal: NgbModal,
+    ) {}
+
+    public readonly url: string = '/api/user/login';
+
+    login(): Observable<Token> {
+        let modal = this.ngbModal.open(LoginModalComponent);
+
+        sessionStorage.clear();
+
+        let observable: Observable<any> = Observable.fromPromise(modal.result);
+
+        return observable.flatMap((login: Login) =>
+            this.doLogin(login)
+        ).map((token: Token): Token => {
+            this.accessToken = token.access_token;
+            return token;
+        });
+    }
+
+    logout() {
+        sessionStorage.clear();
+    }
+
+    doLogin(login: Login): Observable<any> {
+        var authdata = base64.encode(
+            `${login.email}:${login.password}`
+        );
+
+        let headers = new HttpHeaders()
+        headers = headers.set('Authorization', `Basic ${authdata}`);
+
+        this.logger.log("Headers", headers);
+
+        return this.httpClient.post(this.url, {}, {
+            headers: headers
+        });
+    }
+
+    get accessToken(): string {
         return sessionStorage.getItem('access_token');
     }
+
+    set accessToken(token: string) {
+        sessionStorage.setItem('access_token', token);
+    }
 };
diff --git a/src/login/loginForm.component.ts b/src/login/loginForm.component.ts
new file mode 100644
index 0000000..078f940
--- /dev/null
+++ b/src/login/loginForm.component.ts
@@ -0,0 +1,33 @@
+// vim: set tw=80 ts=2 sw=2 sts=2 :
+
+import { Component, Input } from '@angular/core';
+import { NgForm } from '@angular/forms';
+
+import { Login } from './login';
+
+@Component({
+  selector: 'form[login-form]',
+  template: `
+<div class="form-group">
+  <label for="email" class="col-sm-4 control-label">Adresse email</label>
+
+  <div class="col-sm-8">
+    <input type="text" class="form-control" id="email"
+      [(ngModel)]="login.email" placeholder="Nom d'utilisateur">
+  </div>
+</div>
+
+<div class="form-group">
+  <label for="password" class="col-sm-4 control-label">Mot de passe</label>
+
+  <div class="col-sm-8">
+    <input type="password" class="form-control" id="password"
+      [(ngModel)]="login.password" placeholder="Mot de passe">
+  </div>
+</div>
+  `
+})
+
+export class LoginForm {
+  @Input('login-form') private login: Login
+}
diff --git a/src/login/loginModal.component.ts b/src/login/loginModal.component.ts
new file mode 100644
index 0000000..7d4650e
--- /dev/null
+++ b/src/login/loginModal.component.ts
@@ -0,0 +1,47 @@
+// vim: set tw=80 ts=2 sw=2 sts=2:
+
+import { Component } from '@angular/core'
+
+import { NgbActiveModal } from '@ng-bootstrap/ng-bootstrap';
+
+import { Login } from './login';
+
+@Component({
+  selector: 'login-modal',
+  template: `
+<div class="modal-header">
+  <h3 class="modal-title" id="modal-title">Authentification requise</h3>
+</div>
+
+<div class="modal-body" id="modal-body">
+  <form [(login-form)]="login" class="form-horizontal"
+    (ngSubmit)="submit()" #form="ngForm">
+  </form>
+</div>
+
+<div class="modal-footer">
+  <button class="btn btn-primary" [disabled]="!form.valid" (click)="submit()">
+    Login
+  </button>
+
+  <button class="btn btn-default" (click)="cancel()">
+    Cancel
+  </button>
+</div>
+  `
+})
+export class LoginModalComponent {
+  private login: Login = new Login();
+
+  constructor(private activeModal: NgbActiveModal) {
+    
+  }
+
+  submit(): void {
+    this.activeModal.close(this.login);
+  }
+
+  cancel(): void {
+    this.activeModal.dismiss("closed");
+  }
+}
diff --git a/src/login/token.ts b/src/login/token.ts
new file mode 100644
index 0000000..bd6902d
--- /dev/null
+++ b/src/login/token.ts
@@ -0,0 +1,6 @@
+// vim: set tw=80 ts=2 sw=2 sts=2 :
+
+export class Token {
+  access_token: string;
+  refresh_token: string;
+}