diff --git a/app/models/author.rb b/app/models/author.rb
index e399202..9f3a806 100644
--- a/app/models/author.rb
+++ b/app/models/author.rb
@@ -1,2 +1,4 @@
 class Author < ApplicationRecord
+  validates :first_name, presence: true
+  validates :last_name, presence: true
 end
diff --git a/app/models/book.rb b/app/models/book.rb
index 1b16bc8..860c5d5 100644
--- a/app/models/book.rb
+++ b/app/models/book.rb
@@ -2,4 +2,7 @@ class Book < ApplicationRecord
   has_and_belongs_to_many :authors
 
   scope :published, -> { where(published: true) }
+  validates :title, presence: true
+  validates :price, presence: true
+  validates :published, presence: true
 end