function checkform ( form )
{
  // ** START **
  if (form.first_name.value == "") {
    alert( "Please enter your first name." );
    form.first_name.focus();
    return false ;
  }
  
  if (form.last_name.value == "") {
    alert( "Please enter your last name" );
    form.last_name.focus();
    return false ;
  }

  if (form.company_name.value == "") {
    alert( "Please enter your company name" );
    form.company_name.focus();
    return false ;
  }

  if (form.house_no.value == "") {
    alert( "Please enter your house number" );
    form.house_no.focus();
    return false ;
  }
  
  if (form.address1.value == "") {
    alert( "Please enter your address" );
    form.address1.focus();
    return false ;
  }
  
  if (form.town.value == "") {
    alert( "Please enter your town" );
    form.town.focus();
    return false ;
  }
  
  if (form.county.value == "") {
    alert( "Please enter your county" );
    form.county.focus();
    return false ;
  }
  
  if (form.postcode.value == "") {
    alert( "Please enter your postcode" );
    form.postcode.focus();
    return false ;
  }

  if (form.telephone_number.value == "") {
    alert( "Please enter your telephone number" );
    form.telephone_number.focus();
    return false ;
  }
  if (form.email_address.value == "") {
    alert( "Please enter your email address" );
    form.email_address.focus();
    return false ;
  }
  if (form.postcode.value == "") {
    alert( "Please enter your postcode" );
    form.postcode.focus();
    return false ;
  }
  // ** END **
  return true ;
}