Entropy and the second law of thermodynamics are the central organizing principles of nature. Or perhaps more accurately, the second law is the central disorganizing principle. Hot things cool down. Cold things warm up. You cannot get something for nothing. You always pay more than you get. Things fall apart. You cannot repeat the past. We grow old and die. It is all downhill from here to the heat death of the universe. While at first these seem like grim and pessimistic ideas, a deeper understanding reveals that the disequilibrial processes of increasing entropy are what enables all organizing actions, such as the formation of a molecule, building of a cell, birth of a child, organization of an ecosystem. Yet strangely, the ideas and implications of the second law are poorly developed in the landscape ecology literature. This is particularly strange given the focus of landscape ecology on understanding pattern-process relationships across scales in space and time. Every interaction between entities leads to irreversible change which increases the entropy and decreases the free energy of the closed system in which they reside. This is the essence of the entropy principle. Descriptions of landscape patterns, processes of landscape change, propagation of pattern-process relationships across space and through time are all governed, constrained, and in large part directed by thermodynamics. This direct linkage to thermodynamics and entropy was noted in several of the pioneering works in the field of landscape ecology (e.g. Forman and Godron 1986; O'Neill et al. 1986; Naveh 1987; O'neill et al. 1989). Yet in the subsequent decades our field has largely failed to embrace and utilize these relationships and constraints, with a few exceptions (see Wu and Loucks 1995; Zhang and Wu 2002; Zurlini et al. 2013).