Final answer:
Countries with universal health care systems may provide some medical services without the need for gatekeepers or referrals, but 'no wait times' and 'no appointment necessary' are challenging to guarantee due to varying demand and resource availability.
Step-by-step explanation:
The question seems to be asking about health care systems in various countries that allow people to receive medical attention without any barriers such as gatekeepers, wait times, and the need for appointments. It's challenging to name specific countries that meet all these criteria because health care systems are complex and can vary greatly even within a country. However, countries with more liberal or direct-access healthcare systems may come closer to this description. For example, in some countries with universal health care models, such as the United Kingdom's National Health Service (NHS), patients can access certain health services without referrals ('no gatekeepers'). However, 'no wait times' is more difficult to achieve due to demand and limited resources, and 'no appointment necessary' can depend on the type of healthcare provider and the urgency of the situation. It's essential to note that even in countries with high levels of access, emergency services are typically the ones most consistently available without an appointment.