I conducted field work (1) on Warrungu and a few other languages on Palm Island and in the adjacent area of mainland Queensland, three times from 1971 to 1974, and (2) on Djaru and a few other languages in and around Halls Creek, Kimberley, Western Australia, four times from 1975 to 1995. Almost all of the languages I worked on in the 70's were already endangered at that time and many of them have since become extinct. The last speakers of those languages were generally eager to have their language recorded before they passed away. One outstanding example is the late Alf Palmer (Warrungu name: Dyinbilnggay), who used to say to me, ‘I am the last one who can speak this language. When I die, it will die. I teach you everything I know, so put it down properly’. Aboriginal people like the late Alf Palmer have taught me what role scholars should play in relation to the society and humankind. It was fortunate that I was able to obtain the cooperation of people like Alf Palmer and to document their languages. It is my hope that more linguists will study endangered languages and languages of minority poeples in Australia and elsewhere.