Adding non-entity fields to your Symfony2 forms

// in your buildForm() method:
$builder
->add("firstName", "text")
->add("lastName", "text")
->add("emailAddress", "email")
->add("t_and_c", "checkbox", array(
"mapped" => false,
"constraints" => new True(array(
"message" => "Please accept the Terms and conditions in order to register")
),
)
);