Probably works somewhat ok for hotels in cases where they cannot rely on their own online booking facilities. However, way too bad for the holiday rentals market: I've booked in one place, 1 month later the owner of the place decided to cancel the booking, offered an option outside of booking.com (dodgy at the very best), then Booking.com began harassing me with "alternatives" nowhere near to the original booking, including the alternative that was completely outside of their system. They just wanted a quick buck on the booking and me to sort out the moronic response from the owner of the property. Never again, booking.com