diff --git a/app/models/dossier.rb b/app/models/dossier.rb
index bbfc893fe..105d19bc4 100644
--- a/app/models/dossier.rb
+++ b/app/models/dossier.rb
@@ -35,7 +35,8 @@ class Dossier < ApplicationRecord
 
   has_many :dossier_operation_logs, dependent: :destroy
 
-  belongs_to :procedure
+  belongs_to :groupe_instructeur
+  has_one :procedure, through: :groupe_instructeur
   belongs_to :user
 
   accepts_nested_attributes_for :champs
@@ -167,7 +168,7 @@ class Dossier < ApplicationRecord
 
   before_validation :update_state_dates, if: -> { state_changed? }
 
-  before_save :build_default_champs, if: Proc.new { procedure_id_changed? }
+  before_save :build_default_champs, if: Proc.new { groupe_instructeur_id_changed? }
   before_save :build_default_individual, if: Proc.new { procedure.for_individual? }
   before_save :update_search_terms
 
diff --git a/app/models/groupe_instructeur.rb b/app/models/groupe_instructeur.rb
index dcb8a14de..af5c5eaab 100644
--- a/app/models/groupe_instructeur.rb
+++ b/app/models/groupe_instructeur.rb
@@ -3,4 +3,5 @@ class GroupeInstructeur < ApplicationRecord
   belongs_to :procedure
   has_many :assign_tos
   has_many :instructeurs, through: :assign_tos
+  has_many :dossiers
 end
diff --git a/app/models/instructeur.rb b/app/models/instructeur.rb
index df7cde3c2..bf2d29590 100644
--- a/app/models/instructeur.rb
+++ b/app/models/instructeur.rb
@@ -10,9 +10,9 @@ class Instructeur < ApplicationRecord
   has_many :procedures, through: :groupe_instructeurs
 
   has_many :assign_to_with_email_notifications, -> { with_email_notifications }, class_name: 'AssignTo', inverse_of: :instructeur
-  has_many :procedures_with_email_notifications, through: :assign_to_with_email_notifications, source: :procedure
+  has_many :groupe_instructeur_with_email_notifications, through: :assign_to_with_email_notifications, source: :groupe_instructeur
 
-  has_many :dossiers, -> { state_not_brouillon }, through: :procedures
+  has_many :dossiers, -> { state_not_brouillon }, through: :groupe_instructeurs
   has_many :follows, -> { active }, inverse_of: :instructeur
   has_many :previous_follows, -> { inactive }, class_name: 'Follow', inverse_of: :instructeur
   has_many :followed_dossiers, through: :follows, source: :dossier
@@ -115,13 +115,13 @@ class Instructeur < ApplicationRecord
   def notifications_for_procedure(procedure, state = :en_cours)
     dossiers = case state
     when :termine
-      procedure.dossiers.termine
+      procedure.defaut_groupe_instructeur.dossiers.termine
     when :not_archived
-      procedure.dossiers.not_archived
+      procedure.defaut_groupe_instructeur.dossiers.not_archived
     when :all
-      procedure.dossiers
+      procedure.defaut_groupe_instructeur.dossiers
     else
-      procedure.dossiers.en_cours
+      procedure.defaut_groupe_instructeur.dossiers.en_cours
     end
 
     dossiers_id_with_notifications(dossiers)
@@ -137,7 +137,7 @@ class Instructeur < ApplicationRecord
       Dossier.en_cours
     end
 
-    Dossier.where(id: dossiers_id_with_notifications(dossiers)).group(:procedure_id).count
+    Dossier.joins(:groupe_instructeur).where(id: dossiers_id_with_notifications(dossiers)).group('groupe_instructeurs.procedure_id').count
   end
 
   def create_trusted_device_token
@@ -203,11 +203,13 @@ class Instructeur < ApplicationRecord
   end
 
   def email_notification_data
-    procedures_with_email_notifications
-      .reduce([]) do |acc, procedure|
+    groupe_instructeur_with_email_notifications
+      .reduce([]) do |acc, groupe|
+
+      procedure = groupe.procedure
 
       h = {
-        nb_en_construction: procedure.dossiers.en_construction.count,
+        nb_en_construction: groupe.dossiers.en_construction.count,
         nb_notification: notifications_for_procedure(procedure, :all).count
       }
 
diff --git a/app/models/procedure.rb b/app/models/procedure.rb
index a340bf53a..b721afe24 100644
--- a/app/models/procedure.rb
+++ b/app/models/procedure.rb
@@ -5,7 +5,6 @@ class Procedure < ApplicationRecord
 
   has_many :types_de_champ, -> { root.public_only.ordered }, inverse_of: :procedure, dependent: :destroy
   has_many :types_de_champ_private, -> { root.private_only.ordered }, class_name: 'TypeDeChamp', inverse_of: :procedure, dependent: :destroy
-  has_many :dossiers, dependent: :restrict_with_exception
   has_many :deleted_dossiers, dependent: :destroy
 
   has_one :module_api_carto, dependent: :destroy
@@ -18,6 +17,8 @@ class Procedure < ApplicationRecord
   has_many :administrateurs, through: :administrateurs_procedures, after_remove: -> (procedure, _admin) { procedure.validate! }
   has_many :groupe_instructeurs, dependent: :destroy
 
+  has_many :dossiers, through: :groupe_instructeurs, dependent: :restrict_with_exception
+
   has_one :initiated_mail, class_name: "Mails::InitiatedMail", dependent: :destroy
   has_one :received_mail, class_name: "Mails::ReceivedMail", dependent: :destroy
   has_one :closed_mail, class_name: "Mails::ClosedMail", dependent: :destroy
@@ -118,7 +119,7 @@ class Procedure < ApplicationRecord
     if locked?
       raise "Can not reset a locked procedure."
     else
-      dossiers.destroy_all
+      groupe_instructeurs.each { |gi| gi.dossiers.destroy_all }
     end
   end
 
diff --git a/app/serializers/individual_serializer.rb b/app/serializers/individual_serializer.rb
index b7b3032a5..0ef0f4207 100644
--- a/app/serializers/individual_serializer.rb
+++ b/app/serializers/individual_serializer.rb
@@ -4,6 +4,6 @@ class IndividualSerializer < ActiveModel::Serializer
   attribute :birthdate, key: :date_naissance, if: :include_birthdate?
 
   def include_birthdate?
-    object&.dossier&.procedure&.ask_birthday
+    object&.dossier&.groupe_instructeur&.procedure&.ask_birthday
   end
 end
diff --git a/app/services/administrateur_usage_statistics_service.rb b/app/services/administrateur_usage_statistics_service.rb
index 6fc01339b..44d5cba6a 100644
--- a/app/services/administrateur_usage_statistics_service.rb
+++ b/app/services/administrateur_usage_statistics_service.rb
@@ -131,10 +131,10 @@ class AdministrateurUsageStatisticsService
     result = {}
 
     Dossier
-      .joins(procedure: [:administrateurs])
+      .joins(groupe_instructeur: { procedure: [:administrateurs] })
       .group(
         'administrateurs.id',
-        :procedure_id,
+        'groupe_instructeurs.procedure_id',
         <<~EOSQL
           CASE
             WHEN state IN('accepte', 'refuse', 'sans_suite') THEN 'termine'
diff --git a/app/views/commencer/show.html.haml b/app/views/commencer/show.html.haml
index 1f584df63..ee3564f92 100644
--- a/app/views/commencer/show.html.haml
+++ b/app/views/commencer/show.html.haml
@@ -11,7 +11,7 @@
     = render partial: 'shared/france_connect_login', locals: { url: commencer_france_connect_path(path: @procedure.path) }
 
   - else
-    - dossiers = current_user.dossiers.where(procedure: @procedure)
+    - dossiers = current_user.dossiers.where(groupe_instructeur: @procedure.groupe_instructeurs)
     - drafts = dossiers.merge(Dossier.state_brouillon)
     - not_drafts = dossiers.merge(Dossier.state_not_brouillon)
 
diff --git a/db/migrate/20190822143413_add_groupe_instructeur_id_column_to_dossier.rb b/db/migrate/20190822143413_add_groupe_instructeur_id_column_to_dossier.rb
new file mode 100644
index 000000000..2c1240bb7
--- /dev/null
+++ b/db/migrate/20190822143413_add_groupe_instructeur_id_column_to_dossier.rb
@@ -0,0 +1,5 @@
+class AddGroupeInstructeurIdColumnToDossier < ActiveRecord::Migration[5.2]
+  def change
+    add_reference :dossiers, :groupe_instructeur, foreign_key: true
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index a2ee405e7..39061aa04 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2019_08_19_145355) do
+ActiveRecord::Schema.define(version: 2019_08_22_143413) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -275,8 +275,10 @@ ActiveRecord::Schema.define(version: 2019_08_19_145355) do
     t.datetime "hidden_at"
     t.text "search_terms"
     t.text "private_search_terms"
+    t.bigint "groupe_instructeur_id"
     t.index "to_tsvector('french'::regconfig, (search_terms || private_search_terms))", name: "index_dossiers_on_search_terms_private_search_terms", using: :gin
     t.index "to_tsvector('french'::regconfig, search_terms)", name: "index_dossiers_on_search_terms", using: :gin
+    t.index ["groupe_instructeur_id"], name: "index_dossiers_on_groupe_instructeur_id"
     t.index ["hidden_at"], name: "index_dossiers_on_hidden_at"
     t.index ["procedure_id"], name: "index_dossiers_on_procedure_id"
     t.index ["user_id"], name: "index_dossiers_on_user_id"
@@ -648,6 +650,7 @@ ActiveRecord::Schema.define(version: 2019_08_19_145355) do
   add_foreign_key "dossier_operation_logs", "bill_signatures"
   add_foreign_key "dossier_operation_logs", "dossiers"
   add_foreign_key "dossier_operation_logs", "instructeurs"
+  add_foreign_key "dossiers", "groupe_instructeurs"
   add_foreign_key "dossiers", "users"
   add_foreign_key "feedbacks", "users"
   add_foreign_key "geo_areas", "champs"
diff --git a/lib/tasks/2019_06_06_fix_timestamps_of_migrated_dossiers.rake b/lib/tasks/2019_06_06_fix_timestamps_of_migrated_dossiers.rake
index 42688fa49..b563540e6 100644
--- a/lib/tasks/2019_06_06_fix_timestamps_of_migrated_dossiers.rake
+++ b/lib/tasks/2019_06_06_fix_timestamps_of_migrated_dossiers.rake
@@ -4,7 +4,7 @@ namespace :fix_timestamps_of_migrated_dossiers do
   desc 'Fix the timestamps of dossiers affected by the faulty PJ migration'
   task run: :environment do
     affected_time_range = Time.utc(2019, 6, 4, 8, 0)..Time.utc(2019, 6, 4, 18, 0)
-    dossiers = Dossier.unscoped.where(procedure_id: 0..1000).where(updated_at: affected_time_range)
+    dossiers = Dossier.unscoped.includes(:groupe_instructeur).where(groupe_instructeurs: { procedure_id: 0..1000 }).where(updated_at: affected_time_range)
 
     progress = ProgressReport.new(dossiers.count)
 
diff --git a/spec/controllers/instructeurs/procedures_controller_spec.rb b/spec/controllers/instructeurs/procedures_controller_spec.rb
index 48a19ccef..7a2f63bf7 100644
--- a/spec/controllers/instructeurs/procedures_controller_spec.rb
+++ b/spec/controllers/instructeurs/procedures_controller_spec.rb
@@ -344,7 +344,7 @@ describe Instructeurs::ProceduresController, type: :controller do
     context "when logged in" do
       before { sign_in(instructeur.user) }
 
-      it { expect(instructeur.procedures_with_email_notifications).to be_empty }
+      it { expect(instructeur.groupe_instructeur_with_email_notifications).to be_empty }
 
       context 'when the instructeur update its preferences' do
         let(:assign_to) { instructeur.assign_to.find_by(procedure: procedure) }
@@ -353,7 +353,7 @@ describe Instructeurs::ProceduresController, type: :controller do
           patch :update_email_notifications, params: { procedure_id: procedure.id, assign_to: { id: assign_to.id, email_notifications_enabled: true } }
         end
 
-        it { expect(instructeur.procedures_with_email_notifications).to eq([procedure]) }
+        it { expect(instructeur.groupe_instructeur_with_email_notifications).to eq([procedure.defaut_groupe_instructeur]) }
       end
     end
   end
diff --git a/spec/models/dossier_spec.rb b/spec/models/dossier_spec.rb
index eceea782a..1222e3c22 100644
--- a/spec/models/dossier_spec.rb
+++ b/spec/models/dossier_spec.rb
@@ -14,7 +14,7 @@ describe Dossier do
 
   describe 'with_champs' do
     let(:procedure) { create(:procedure) }
-    let(:dossier) { Dossier.create(user: create(:user), procedure: procedure) }
+    let(:dossier) { Dossier.create(user: create(:user), groupe_instructeur: procedure.defaut_groupe_instructeur) }
 
     before do
       create(:type_de_champ, libelle: 'l1', order_place: 1, procedure: procedure)
@@ -189,7 +189,7 @@ describe Dossier do
 
   describe '#champs' do
     let(:procedure) { create(:procedure) }
-    let(:dossier) { Dossier.create(user: create(:user), procedure: procedure) }
+    let(:dossier) { Dossier.create(user: create(:user), groupe_instructeur: procedure.defaut_groupe_instructeur) }
 
     before do
       create(:type_de_champ, libelle: 'l1', order_place: 1, procedure: procedure)
@@ -202,7 +202,7 @@ describe Dossier do
 
   describe '#champs_private' do
     let(:procedure) { create :procedure }
-    let(:dossier) { Dossier.create(user: create(:user), procedure: procedure) }
+    let(:dossier) { Dossier.create(user: create(:user), groupe_instructeur: procedure.defaut_groupe_instructeur) }
 
     before do
       create :type_de_champ, :private, libelle: 'l1', order_place: 1, procedure: procedure
@@ -400,7 +400,7 @@ describe Dossier do
       dossier = nil
       expect do
         perform_enqueued_jobs do
-          dossier = Dossier.create(procedure: procedure, state: Dossier.states.fetch(:brouillon), user: user)
+          dossier = Dossier.create(groupe_instructeur: procedure.defaut_groupe_instructeur, state: Dossier.states.fetch(:brouillon), user: user)
         end
       end.to change(ActionMailer::Base.deliveries, :size).from(0).to(1)
 
@@ -410,11 +410,11 @@ describe Dossier do
     end
 
     it "does not send an email when the dossier is created with a non brouillon state" do
-      expect { Dossier.create(procedure: procedure, state: Dossier.states.fetch(:en_construction), user: user) }.not_to change(ActionMailer::Base.deliveries, :size)
-      expect { Dossier.create(procedure: procedure, state: Dossier.states.fetch(:en_instruction), user: user) }.not_to change(ActionMailer::Base.deliveries, :size)
-      expect { Dossier.create(procedure: procedure, state: Dossier.states.fetch(:accepte), user: user) }.not_to change(ActionMailer::Base.deliveries, :size)
-      expect { Dossier.create(procedure: procedure, state: Dossier.states.fetch(:refuse), user: user) }.not_to change(ActionMailer::Base.deliveries, :size)
-      expect { Dossier.create(procedure: procedure, state: Dossier.states.fetch(:sans_suite), user: user) }.not_to change(ActionMailer::Base.deliveries, :size)
+      expect { Dossier.create(groupe_instructeur: procedure.defaut_groupe_instructeur, state: Dossier.states.fetch(:en_construction), user: user) }.not_to change(ActionMailer::Base.deliveries, :size)
+      expect { Dossier.create(groupe_instructeur: procedure.defaut_groupe_instructeur, state: Dossier.states.fetch(:en_instruction), user: user) }.not_to change(ActionMailer::Base.deliveries, :size)
+      expect { Dossier.create(groupe_instructeur: procedure.defaut_groupe_instructeur, state: Dossier.states.fetch(:accepte), user: user) }.not_to change(ActionMailer::Base.deliveries, :size)
+      expect { Dossier.create(groupe_instructeur: procedure.defaut_groupe_instructeur, state: Dossier.states.fetch(:refuse), user: user) }.not_to change(ActionMailer::Base.deliveries, :size)
+      expect { Dossier.create(groupe_instructeur: procedure.defaut_groupe_instructeur, state: Dossier.states.fetch(:sans_suite), user: user) }.not_to change(ActionMailer::Base.deliveries, :size)
     end
   end