Among the many contributions of Roderick D. McKenzie to sociology are two ideas which continue to be useful in understanding modern society. First, as the main proponent and theorist of the human ecology of the Chicago School, McKenzie offers suggestions for an alternative conception of society, one that emphasizes among other things the physical basis of social relations. Secondly, McKenzie's works suggest in various ways that modern society is characterized by a growth in physical integration. The first aspect of this argument is found in his discussion of the centrality of institutions in the analysis of social relations. The second aspect is his detailed description and analysis of the “great integrated unity“ that he called the Great Society or World Society. Many decades before sociologists began to write of “globalization,“ McKenzie provides detailed description and extensive analysis of global society and many of the issues in the current globalization debate.