Nice in theory, but apparently a complete failure in practice. I showed up to an appointment I really needed (booked and confirmed through zocdoc) for a doctor's office who had never heard of me! Not only did they not have me in their system at all, this is apparently a frequent occurance. The first thing I was asked was, "uh oh, did you use zocdoc?" Personally, I think doctor's offices need to stop using this service if it's flawed enough for them to not be surprised when patients get lost in the system!