So far improvements in technology and crop yields have enabled food output to keep pace with the population in most of the world - just. But, the authors argue, most of the available improvements have been made, and there is already over-harvesting in areas such as fishing. Thus, the only strategy is to over-pump and over-plow, a setting on a course to disaster. The authors sound an important warning note about this dangerous course and argue for steps to be taken now to alter course.