diff --git a/LivreLand/View/DetailsLivreView.xaml b/LivreLand/View/DetailsLivreView.xaml
index 386dba6..de63294 100644
--- a/LivreLand/View/DetailsLivreView.xaml
+++ b/LivreLand/View/DetailsLivreView.xaml
@@ -309,8 +309,8 @@
                     <contentView:SeparatorCutStartView/>
 
                     <contentView:DetailsLivreButtonView ButtonIcon="heart.png"
-                                                        ButtonTitle="Ajouter aux favoris"
-                                                        ButtonCommand="{Binding DetailsLivreVM.AddBookToFavoritesCommand}"
+                                                        ButtonTitle="{Binding DetailsLivreVM.AddFavorisButtonText}"
+                                                        ButtonCommand="{Binding DetailsLivreVM.AddRemoveBookToFavoritesCommand}"
                                                         ButtonCommandParameter="{Binding DetailsLivreVM.Book}"/>
 
                     <contentView:SeparatorCutStartView/>
diff --git a/LivreLand/ViewModel/DetailsLivreVM.cs b/LivreLand/ViewModel/DetailsLivreVM.cs
index 9bb2782..bb1fa0c 100644
--- a/LivreLand/ViewModel/DetailsLivreVM.cs
+++ b/LivreLand/ViewModel/DetailsLivreVM.cs
@@ -1,4 +1,5 @@
 using CommunityToolkit.Maui.Alerts;
+using Model;
 using PersonalMVVMToolkit;
 using System;
 using System.Collections.Generic;
@@ -15,6 +16,7 @@ namespace LivreLand.ViewModel
         #region Fields
 
         private bool isPickerVisible = false;
+        private string addFavorisButtonText;
 
         #endregion
 
@@ -38,10 +40,34 @@ namespace LivreLand.ViewModel
                 }
             }
         }
+        
+        public string AddFavorisButtonText
+        {
+            get
+            {
+                Manager.GetFavoriteBooksCommand.Execute(null);
+                if (Manager.AllFavoriteBooks.Any(favoriteBook => favoriteBook.Id == Book.Id))
+                {
+                    return addFavorisButtonText = "Supprimer des favoris";
+                }
+                else
+                {
+                    return addFavorisButtonText = "Ajouter aux favoris";
+                }
+            }
+            set
+            {
+                if (addFavorisButtonText != value)
+                {
+                    addFavorisButtonText = value;
+                    OnPropertyChanged(nameof(AddFavorisButtonText));
+                }
+            }
+        }
 
         public ICommand ShowPickerCommand { get; private set; }
 
-        public ICommand AddBookToFavoritesCommand { get; private set; }
+        public ICommand AddRemoveBookToFavoritesCommand { get; private set; }
 
         public ICommand AddBookToReadListCommand { get; private set; }
 
@@ -57,7 +83,7 @@ namespace LivreLand.ViewModel
             Navigator = navigatorVM;
             Book = bookVM;
             ShowPickerCommand = new RelayCommand(() => ShowPicker());
-            AddBookToFavoritesCommand = new RelayCommand<BookVM>((bookVM) => AddBookToFavorites(bookVM));
+            AddRemoveBookToFavoritesCommand = new RelayCommand<BookVM>((bookVM) => AddRemoveBookToFavorites(bookVM));
             AddBookToReadListCommand = new RelayCommand<BookVM>((bookVM) => AddBookToReadList(bookVM));
             RemoveBookCommand = new RelayCommand<BookVM>((bookVM) => RemoveBook(bookVM));
         }
@@ -72,14 +98,31 @@ namespace LivreLand.ViewModel
             IsPickerVisible = true;
         }
 
-        private async Task AddBookToFavorites(BookVM bookVM)
+        private async Task AddRemoveBookToFavorites(BookVM bookVM)
         {
-            Manager.AddToFavoritesCommand.Execute(bookVM);
+            Manager.CheckBookIsFavoriteCommand.Execute(bookVM);
+            if (Manager.IsFavorite == false)
+            {
+                Manager.AddToFavoritesCommand.Execute(bookVM);
+                AddFavorisButtonText = "Supprimer des favoris";
+                OnPropertyChanged(nameof(AddFavorisButtonText));
 
-            var toast = Toast.Make("Livre ajouté aux favoris !", CommunityToolkit.Maui.Core.ToastDuration.Short);
-            await toast.Show();
+                var toast = Toast.Make("Livre ajouté aux favoris !", CommunityToolkit.Maui.Core.ToastDuration.Short);
+                await toast.Show();
 
-            Navigator.NavigationCommand.Execute("/favoris");
+                Navigator.NavigationCommand.Execute("/favoris");
+            }
+            else
+            {
+                Manager.RemoveFromFavoritesCommand.Execute(bookVM);
+                AddFavorisButtonText = "Ajouter aux favoris";
+                OnPropertyChanged(nameof(AddFavorisButtonText));
+
+                var toast = Toast.Make("Livre supprimé des favoris !", CommunityToolkit.Maui.Core.ToastDuration.Short);
+                await toast.Show();
+
+                Navigator.NavigationCommand.Execute("/favoris");
+            }
         }
 
         private async Task AddBookToReadList(BookVM bookVM)
diff --git a/LivreLand/ViewModel/TousVM.cs b/LivreLand/ViewModel/TousVM.cs
index 9e995ab..2aff733 100644
--- a/LivreLand/ViewModel/TousVM.cs
+++ b/LivreLand/ViewModel/TousVM.cs
@@ -36,8 +36,11 @@ namespace LivreLand.ViewModel
 
         private void OnSelectionChanged(BookVM bookVM)
         {
-            var result = new DetailsLivreVM(Manager, Navigator, bookVM);
-            App.Current.MainPage.Navigation.PushAsync(new DetailsLivreView(result));
+            if (bookVM != null)
+            {
+                var result = new DetailsLivreVM(Manager, Navigator, bookVM);
+                App.Current.MainPage.Navigation.PushAsync(new DetailsLivreView(result));
+            }
         }
 
         #endregion
diff --git a/ViewModels/ManagerVM.cs b/ViewModels/ManagerVM.cs
index 5c623f6..c9ee959 100644
--- a/ViewModels/ManagerVM.cs
+++ b/ViewModels/ManagerVM.cs
@@ -36,6 +36,8 @@ namespace ViewModels
 
         private string givenFirstName;
         private string givenLastName;
+        private bool isFavorite;
+
         #endregion
 
         #region Properties 
@@ -204,6 +206,19 @@ namespace ViewModels
             }
         }
 
+        public bool IsFavorite
+        {
+            get { return isFavorite; }
+            set
+            {
+                if (isFavorite != value)
+                {
+                    isFavorite = value;
+                    OnPropertyChanged(nameof(IsFavorite));
+                }
+            }
+        }
+
         public string SearchTitle { get; private set; }
 
         public int Index 
@@ -264,6 +279,8 @@ namespace ViewModels
 
         public ICommand RemoveFromFavoritesCommand { get; private set; }
 
+        public ICommand CheckBookIsFavoriteCommand { get; private set; }
+
         public ICommand GetCurrentLoansCommand { get; private set; }
 
         public ICommand GetPastLoansCommand { get; private set; }
@@ -302,6 +319,7 @@ namespace ViewModels
             GetFavoriteBooksCommand = new RelayCommand(() => GetFavoriteBooks());
             AddToFavoritesCommand = new RelayCommand<BookVM>(bookVM => AddToFavorites(bookVM));
             RemoveFromFavoritesCommand = new RelayCommand<BookVM>(bookVM => RemoveFromFavorites(bookVM));
+            CheckBookIsFavoriteCommand = new RelayCommand<BookVM>(bookVM => CheckBookIsFavorite(bookVM));
             GetCurrentLoansCommand = new RelayCommand(() =>  GetCurrentLoans());
             GetPastLoansCommand = new RelayCommand(() =>  GetPastLoans());
             GetCurrentBorrowingsCommand = new RelayCommand(() => GetCurrentBorrowings());
@@ -556,6 +574,21 @@ namespace ViewModels
             await GetFavoriteBooks();
         }
 
+        private async Task CheckBookIsFavorite(BookVM bookVM)
+        {
+            await GetFavoriteBooks();
+            if (AllFavoriteBooks.Any(favoriteBook => favoriteBook.Id == bookVM.Id))
+            {
+                IsFavorite = true;
+                OnPropertyChanged(nameof(IsFavorite));
+            }
+            else
+            {
+                IsFavorite = false;
+                OnPropertyChanged(nameof(IsFavorite));
+            }
+        }
+
         private async Task GetCurrentLoans()
         {
             var result = await Model.GetCurrentLoans(0, 20);