diff --git a/Interface.py b/Interface.py
index e5656f3..964668f 100644
--- a/Interface.py
+++ b/Interface.py
@@ -15,9 +15,9 @@ class Interface(tk.Tk):
         tk.Label(text="Message reçu : ").pack()
         self.message = tk.StringVar()
         tk.Label(textvariable=self.message).pack()
-        self.sendButton = tk.Button(self, text="Send", command=self.send)
+        self.sendButton = tk.Button(self, text="Send", command=self.send, state="disabled")
         self.sendButton.pack()
-        self.recvButton = tk.Button(self, text="Receive", command=self.receive)
+        self.recvButton = tk.Button(self, text="Receive", command=self.receive, state="disabled")
         self.recvButton.pack()
         #
         self._cleSymetrique = None
diff --git a/InterfaceClient.py b/InterfaceClient.py
index e3d2310..a74d554 100644
--- a/InterfaceClient.py
+++ b/InterfaceClient.py
@@ -11,13 +11,15 @@ class InterfaceClient(Interface):
         # à compléter
         self.sendHelloButton = tk.Button(self, text="Hello", command=self.hello)
         self.sendHelloButton.pack()
-        self.keyExchangeButton = tk.Button(self, text="KeyExchange", command=self.keyExchange)
+        self.keyExchangeButton = tk.Button(self, text="KeyExchange", command=self.keyExchange, state="disabled")
         self.keyExchangeButton.pack()
-        
+    
     def hello(self):
         """envoie en clair le message HELLO"""
         self.entree.set("HELLO")
         self.send()
+        self.sendHelloButton['state'] = "disabled"
+        self.keyExchangeButton['state'] = "enable"
         
     def keyExchange(self):
         """attend la clé publique du serveur
@@ -39,6 +41,9 @@ class InterfaceClient(Interface):
         self.receive()
         if self.message.get() == "Finished":
             print("Connection sécurisée établie ☺")
+            self.keyExchangeButton['state'] = "disabled"
+            self.sendButton['state'] = "enabled"
+            self.recvButton['state'] = "enabled"
         
     def chiffre_RSA(self, msg, cle):
         """chiffre un message avec une clé publique"""
diff --git a/InterfaceServeur.py b/InterfaceServeur.py
index 0f69c1b..bbe6cc7 100644
--- a/InterfaceServeur.py
+++ b/InterfaceServeur.py
@@ -13,7 +13,7 @@ class InterfaceServeur(Interface):
         # à compléter
         self.waitForHelloButton = tk.Button(self, text="Serveur Hello", command=self.hello)
         self.waitForHelloButton.pack()
-        self.finishedButton = tk.Button(self, text="Finished", command=self.finish)
+        self.finishedButton = tk.Button(self, text="Finished", command=self.finish, state="disabled")
         self.finishedButton.pack()
         
     def hello(self):
@@ -23,6 +23,8 @@ class InterfaceServeur(Interface):
         if self.message.get() == "HELLO":
             self.entree.set(str(self.e)+";"+str(self.n))
             self.send()
+            self.waitForHelloButton['state'] = 'disabled'
+            self.finishedButton['state'] = 'enabled'
         else:
             print("HELLO n'a pas été reçu.")
             
@@ -35,6 +37,9 @@ class InterfaceServeur(Interface):
         self.set_cleSymetrique(cleSym_dechiffree) 
         self.entree.set("Finished")
         self.send()
+        self.finishedButton['state'] = "disabled"
+        self.sendButton['state'] = "enabled"
+        self.recvButton['state'] = "enabled"
         
     def dechiffre_RSA(self, msg):
         """déchiffre un message avec sa clé privée"""