BuddyPress.org

Check out the template file `register.php`, located in `buddypress/bp-themes/bp-default/registration/register.php`. You have a couple possible strategies:

1) Copy register.php to your child theme and add hidden inputs directly in the markup
2) Hook to one of the many do_actions littered through the code to add your fields. Eg
`function bbg_add_reg_field() {
echo ”;
}
add_action( ‘bp_before_registration_submit_buttons’, ‘bbg_add_reg_field’ );`

Then you’ll have to catch the data being sent. I recommend doing something like this
`function bbg_grab_reg_data() {
if ( isset( $_POST ) ) {
// do something with the custom data
}
}
add_action( ‘bp_complete_signup’, ‘bbg_grab_reg_data’ );`