Skilful means (upàya kosalla) is a teacher's willingness to adapt to the interests, needs and level of understanding of others, in order to successfully communicate the Dhamma to them (D.III,220; Th.158). At their best, skilful means are a type of flexibility and sympathy. The Sutta Nipàta describes a good teacher as being `skilled in knowing the means' (upàya¤¤u kusalo, Sn.321). The Buddha said he would adapt his speech and even his appearance to be better able to teach the Dhamma to different types of people: `I remember well many assemblies of patricians, priests, householders, ascetics and gods that I have attended. Before I sat with them, spoke to them or joined their conversation, I adopted their appearance and their speech whatever it might be and then I instructed them in Dhamma'(D.II,109).The Buddha told his monks and nuns that when teaching Dhamma in foreign parts they should adopt the language of the people they were living with (M.III,235).
A good example of the Buddha's skilful means was his encounter with Sigàla as recorded in the Sigàlovàda Sutta. One day he saw this young man worshipping the six directions, a common religious practice at that time. He asked Sigàla why he was doing this and the young man replied that his father, on his death bed, had made him promise to do it and thus continue a family tradition. Although the Buddha had little regard for such practices, he could see that Sigàla's intentions were good, that he was worshipping the directions out of respect for his father, and keeping the promise he had made to him. So rather than criticize or condemn the practice, he asked Sigàla to modify it slightly, to see the people he had relationships with; his parents, children, friends, employees, teachers, etc, as equivalent to the directions and to worship them by treating them with kindness, respect and love (D.III,181).