Articulating the laws of cognitive work has been a continuing theme in this department. A number of the articles represent an effort to move toward a unified theory of "macrocognitive work systems." These are complex adaptive systems designed to support near-continuous interdependencies among humans and intelligent machines to carry out functions such as sensemaking, replanning, mental projection to the future, and coordination. The effort to identify empirical generalizations and use them to construct a formal theory has led us to the identification of a number of fundamental trade-offs that place boundary conditions on all macrocognitive work systems. This article presents five trade-offs identified to date that define these boundary conditions. It also illustrates how the known empirical generalizations about the performance of human work systems can be systematically organized by the trade-offs.