What a mind. Half of my book clubs read Managing the Nonprofit Organization this month, and we talked (three days after his death) about the importance of Drucker's weighing in on nonprofit organizations needing to be better managed when he did (1990). As I vividly recall, his ideas (which a bunch of people, including yours truly had been advocating for a decade with no luck), created a firestorm of criticism. People in the field, particularly foundations and large national nonprofits, scoffed at the idea of a charity being businesslike, dissing the concept as unseemly, and bemoaning the "fact" that adopting business techniques would sully the pristine landscape of charities.
Some people still feel that way today, although far fewer, particularly in an era of outcome measures, benchmarking, and transparency. Drucker's name and reputation was so large, so imposing that he really was the father of good nonprofit management.
And we owe him a pause in our busy days to remember that.