Ethics basically involves leading life in a right manner and making right decisions about moral issues. In Buddhism, there is no God. So, it is up to human beings themselves to perform right action and make this world better. Buddhism considers behaviour ethical only if it does not cause harm to one self or other. It is also noteworthy that in Buddhism, ethical beaviour is necessary not only because it is based on right or wrong but also because it is the means to attain enlightenment. For common Buddhists, the Five Precepts form the foundation for an ethical behaviour.
Essentially, according to Buddhist teachings, the ethical and moral principles are governed by examining whether a certain action, whether connected to body or speech is likely to be harmful to one's self or to others and thereby avoiding any actions which are likely to be harmful. In Buddhism, there is much talk of a skilled mind. A mind that is skilful avoids actions that are likely to cause suffering or remorse.