first_or_create by email and then save the nested model
I two models User and Submission as follows: class User < ActiveRecord::Base # Associations has_many :submissions accepts_nested_attributes_for :submissions # Setup accessible (or protected) attributes for your model attr_accessible :email, :name, :role, :submission_ids, :quotation_ids, :submissions_attributes validates :email, :presence => {:message => "Please enter a valid email address" } validates :email, :uniqueness => { :case_sensitive => false } end class Submission < ActiveRecord::Base belongs_to :user attr_accessible :due_date, :text, :title, :word_count, :work_type, :rush, :user,