Complexity is both a buzzword and a paradigm in the biophysical sciences and, increasingly, the social sciences. We define “social complexity” as the nonlinear escalation of costs and emergent infrastructure with rising energy use and concentrated power as societies develop. Two paths to social complexity are technotasking, which relies on technological break-throughs and is often politically hierarchical, and labortasking, which relies on skilled labor pools and is often heterarchical. We suggest several pathways to greater degrees of complexity and present two case studies emphasizing the role of labor-tasking; an in-depth review of the ancient Maya and a shorter introduction to the recent Balinese. Both of these complex societies used labortasking to adapt to local ecological limitations in semitropical settings. These societies used heterarchical organizations to accretionally engineer and manage their environments, strategies that promoted long-term resilience. Case studies such as these provide a nuanced picture of different paths to social complexity and highlight their relative costs, benefits, and potential for long-term sustainability.