In some countries divisive public controversy occurs over the moral, ethical, and legal issues associated with euthanasia. Passive euthanasia (known as "pulling the plug") is legal under some circumstances in many countries. Active euthanasia, however, is legal or "de facto" legal in only a handful of countries (for example: Belgium, Canada and Switzerland), which limit it to specific circumstances and require the approval of counselors and doctors or other specialists. In some countries - such as Nigeria, Saudi Arabia and Pakistan - support for active euthanasia is almost non-existent.