diff --git a/app/models/account.rb b/app/models/account.rb
index 8048a92..c774283 100644
--- a/app/models/account.rb
+++ b/app/models/account.rb
@@ -15,6 +15,8 @@ class Account < ApplicationRecord
 
   has_one :user
 
+  has_many :sessions
+
   #############
   # Callbacks #
   #############
diff --git a/app/models/session.rb b/app/models/session.rb
new file mode 100644
index 0000000..d0bfaed
--- /dev/null
+++ b/app/models/session.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+class Session < ApplicationRecord
+  ################
+  # Associations #
+  ################
+
+  belongs_to :account
+
+  ###############
+  # Validations #
+  ###############
+
+  validates :ip_address, presence: true
+end
diff --git a/db/migrate/20181129203927_initial_migration.rb b/db/migrate/20181129203927_initial_migration.rb
index f034622..45036c4 100644
--- a/db/migrate/20181129203927_initial_migration.rb
+++ b/db/migrate/20181129203927_initial_migration.rb
@@ -266,6 +266,14 @@ private
                    null: false, index: { unique: true }, foreign_key: true
     end
 
+    create_table :sessions do |t|
+      t.timestamps null: false
+
+      t.references :account, null: false, index: true, foreign_key: true
+
+      t.string :ip_address, null: false
+    end
+
     create_table :person_comments do |t|
       t.timestamps null: false
 
@@ -385,6 +393,10 @@ private
   end
 
   def change_constraints
+    constraint :sessions, :ip_address, <<~SQL
+      is_good_small_text(ip_address)
+    SQL
+
     constraint :regional_offices, :name, <<~SQL
       is_good_small_text(name)
     SQL
diff --git a/db/structure.sql b/db/structure.sql
index 3e99dcc..0bacb32 100644
--- a/db/structure.sql
+++ b/db/structure.sql
@@ -728,6 +728,39 @@ CREATE TABLE public.schema_migrations (
 );
 
 
+--
+-- Name: sessions; Type: TABLE; Schema: public; Owner: -
+--
+
+CREATE TABLE public.sessions (
+    id bigint NOT NULL,
+    created_at timestamp(6) without time zone NOT NULL,
+    updated_at timestamp(6) without time zone NOT NULL,
+    account_id bigint NOT NULL,
+    ip_address character varying NOT NULL,
+    CONSTRAINT ip_address CHECK (public.is_good_small_text((ip_address)::text))
+);
+
+
+--
+-- Name: sessions_id_seq; Type: SEQUENCE; Schema: public; Owner: -
+--
+
+CREATE SEQUENCE public.sessions_id_seq
+    START WITH 1
+    INCREMENT BY 1
+    NO MINVALUE
+    NO MAXVALUE
+    CACHE 1;
+
+
+--
+-- Name: sessions_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
+--
+
+ALTER SEQUENCE public.sessions_id_seq OWNED BY public.sessions.id;
+
+
 --
 -- Name: user_omniauths; Type: TABLE; Schema: public; Owner: -
 --
@@ -894,6 +927,13 @@ ALTER TABLE ONLY public.regional_offices ALTER COLUMN id SET DEFAULT nextval('pu
 ALTER TABLE ONLY public.relationships ALTER COLUMN id SET DEFAULT nextval('public.relationships_id_seq'::regclass);
 
 
+--
+-- Name: sessions id; Type: DEFAULT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY public.sessions ALTER COLUMN id SET DEFAULT nextval('public.sessions_id_seq'::regclass);
+
+
 --
 -- Name: user_omniauths id; Type: DEFAULT; Schema: public; Owner: -
 --
@@ -1020,6 +1060,14 @@ ALTER TABLE ONLY public.schema_migrations
     ADD CONSTRAINT schema_migrations_pkey PRIMARY KEY (version);
 
 
+--
+-- Name: sessions sessions_pkey; Type: CONSTRAINT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY public.sessions
+    ADD CONSTRAINT sessions_pkey PRIMARY KEY (id);
+
+
 --
 -- Name: user_omniauths user_omniauths_pkey; Type: CONSTRAINT; Schema: public; Owner: -
 --
@@ -1239,6 +1287,13 @@ CREATE INDEX index_relationships_on_role ON public.relationships USING btree (ro
 CREATE INDEX index_relationships_on_status ON public.relationships USING btree (status);
 
 
+--
+-- Name: index_sessions_on_account_id; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_sessions_on_account_id ON public.sessions USING btree (account_id);
+
+
 --
 -- Name: index_user_omniauths_on_remote_id_and_provider; Type: INDEX; Schema: public; Owner: -
 --
@@ -1333,6 +1388,14 @@ ALTER TABLE ONLY public.people
     ADD CONSTRAINT fk_rails_4f02f930eb FOREIGN KEY (contact_list_id) REFERENCES public.contact_lists(id);
 
 
+--
+-- Name: sessions fk_rails_5599381559; Type: FK CONSTRAINT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY public.sessions
+    ADD CONSTRAINT fk_rails_5599381559 FOREIGN KEY (account_id) REFERENCES public.accounts(id);
+
+
 --
 -- Name: passports fk_rails_5cdfa39dea; Type: FK CONSTRAINT; Schema: public; Owner: -
 --
diff --git a/factories/sessions.rb b/factories/sessions.rb
new file mode 100644
index 0000000..0a9820e
--- /dev/null
+++ b/factories/sessions.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+FactoryBot.define do
+  factory :some_session, class: Session do
+    association :account, factory: :usual_account
+
+    ip_address { Faker::Internet.ip_v4_address }
+
+    trait :with_ipv6_address do
+      ip_address { Faker::Internet.ip_v6_address }
+    end
+  end
+
+  factory :some_session_with_ipv4_address,
+          parent: :some_session,
+          traits: %i[with_ipv6_address]
+end
diff --git a/spec/models/account_spec.rb b/spec/models/account_spec.rb
index 622acfa..e4b180b 100644
--- a/spec/models/account_spec.rb
+++ b/spec/models/account_spec.rb
@@ -23,6 +23,14 @@ RSpec.describe Account do
     it { is_expected.not_to validate_presence_of :user }
   end
 
+  describe '#sessions' do
+    it do
+      is_expected.to \
+        have_many(:sessions)
+        .dependent(:restrict_with_exception)
+    end
+  end
+
   describe '#person' do
     it { is_expected.to belong_to(:person).optional }
 
diff --git a/spec/models/session_spec.rb b/spec/models/session_spec.rb
new file mode 100644
index 0000000..cb3c48f
--- /dev/null
+++ b/spec/models/session_spec.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe Session do
+  subject { create :some_session }
+
+  describe '#account' do
+    it { is_expected.to belong_to(:account).required }
+
+    it { is_expected.to validate_presence_of(:account).with_message(:required) }
+  end
+
+  describe '#ip_address' do
+    it { is_expected.to validate_presence_of :ip_address }
+  end
+end