I taught AEC 620, Advanced Production Economics, every year between 1974, when I arrived as an assistant professor at the University of Kentucky, to 2012, when I retired. The following publication is one of the early sets of class notes I used in the course, dating from 1978 set up as an early research report. These notes are what evolved into the hard-cover textbook “Agricultural Production Economics” Published by Macmillan in 1986. The 1986 text book evolved into the soft cover 2012 textbook “Agricultural Production Economics Second edition”, available in bound paper volume on Amazon, at college bookstores, and as a free e-download at ageconsearch. It is fun to look at these 1978 notes to see how my thoughts in production economics evolved over nearly 40 years.