diff --git a/app/models/administrateur.rb b/app/models/administrateur.rb
index d23ce1cf4..18ad7e7ae 100644
--- a/app/models/administrateur.rb
+++ b/app/models/administrateur.rb
@@ -9,6 +9,16 @@ class Administrateur < ActiveRecord::Base
 
   include CredentialsSyncableConcern
 
+  scope :inactive, -> { where(active: false) }
+
+  def self.find_inactive_by_token(reset_password_token)
+    self.inactive.with_reset_password_token(reset_password_token)
+  end
+
+  def self.find_inactive_by_id(id)
+    self.inactive.find(id)
+  end
+
   def ensure_api_token
     if api_token.nil?
       self.api_token = generate_api_token
@@ -19,6 +29,46 @@ class Administrateur < ActiveRecord::Base
     update_attributes(api_token: generate_api_token)
   end
 
+  def registration_state
+    if active?
+      'Actif'
+    elsif reset_password_period_valid?
+      'En attente'
+    else
+      'Expiré'
+    end
+  end
+
+  def invite!
+    if active?
+      raise "Impossible d'inviter un utilisateur déjà actif !"
+    end
+    
+    reset_password_token = set_reset_password_token
+  
+    AdministrationMailer.invite_admin(self, reset_password_token).deliver_now!
+
+    reset_password_token
+  end
+
+  def invitation_expired?
+    !active && !reset_password_period_valid?
+  end
+
+  def self.reset_password(reset_password_token, password)
+    administrateur = self.reset_password_by_token({
+      password: password,
+      password_confirmation: password,
+      reset_password_token: reset_password_token
+    })
+
+    if administrateur && administrateur.errors.empty?
+      administrateur.update_column(:active, true)
+    end
+
+    administrateur
+  end
+
   private
 
   def generate_api_token
diff --git a/app/models/administration.rb b/app/models/administration.rb
index f19ea8226..a2e3b56fa 100644
--- a/app/models/administration.rb
+++ b/app/models/administration.rb
@@ -6,4 +6,19 @@ class Administration < ActiveRecord::Base
   def self.from_omniauth(params)
     find_by(email: params["info"]["email"])
   end
+
+  def invite_admin(email)
+    administrateur = Administrateur.new({
+      email: email,
+      active: false 
+    })
+    administrateur.password = administrateur.password_confirmation = SecureRandom.hex
+
+    if administrateur.save
+      AdministrationMailer.new_admin_email(administrateur, self).deliver_now!
+      administrateur.invite!
+    end
+
+    administrateur
+  end
 end
diff --git a/spec/models/administrateur_spec.rb b/spec/models/administrateur_spec.rb
index 65cc16f5f..6fb94c9fc 100644
--- a/spec/models/administrateur_spec.rb
+++ b/spec/models/administrateur_spec.rb
@@ -50,4 +50,20 @@ describe Administrateur, type: :model do
       expect(gestionnaire.valid_password?('super secret')).to be(true)
     end
   end
+
+  describe '#find_inactive_by_token' do
+    let(:administrateur) { create(:administration).invite_admin('paul@tps.fr') }
+    let(:reset_password_token) { administrateur.invite! }
+
+    it { expect(Administrateur.find_inactive_by_token(reset_password_token)).not_to be_nil }
+  end
+
+  describe '#reset_password' do
+    let(:administrateur) { create(:administration).invite_admin('paul@tps.fr') }
+    let(:reset_password_token) { administrateur.invite! }
+
+    it { expect(Administrateur.reset_password(reset_password_token, '12345678').errors).to be_empty }
+    it { expect(Administrateur.reset_password('123', '12345678').errors).not_to be_empty }
+    it { expect(Administrateur.reset_password(reset_password_token, '').errors).not_to be_empty }
+  end
 end
diff --git a/spec/models/administration_spec.rb b/spec/models/administration_spec.rb
new file mode 100644
index 000000000..9f8e0463e
--- /dev/null
+++ b/spec/models/administration_spec.rb
@@ -0,0 +1,17 @@
+require 'spec_helper'
+
+describe Administration, type: :model do
+  describe '#invite_admin' do
+    let(:administration) { create :administration }
+    let(:valid_email) { 'paul@tps.fr' }
+    subject { administration.invite_admin(valid_email) }
+
+    it {
+      expect(subject.errors).to be_empty
+      expect(subject).to be_persisted
+      expect(administration.invite_admin(valid_email).errors).not_to be_empty
+    }
+    it { expect(administration.invite_admin(nil).errors).not_to be_empty }
+    it { expect(administration.invite_admin('toto').errors).not_to be_empty }
+  end
+end