Voluntary programs have rapidly become a means for the public, private, and third sectors to regulate and govern complex societal problems. Following the rapid and widespread emergence of these programs, scholars have been active in mapping, exploring, and interrogating their design and performance. Considerable advances have been made in describing program design and context conditions, and the actors involved in the voluntary program that relate to program performance. Less is known, however, about how these conditions affect program performance. Starting with one of the dominant theories on voluntary programs, the club theory perspective, this article seeks to understand how different program design conditions interact to affect the performance of 26 voluntary programs for low carbon building and city development in Australia, the Netherlands, and the United States. Applying qualitative comparative analysis, the study finds that the club theory perspective has limited explanatory power for this specific set of cases. Iterative rounds of analysis indicate that a diffusion network perspective is the best complementary perspective for explaining the performance of this set of programs. The article concludes that, in situations of a non-homogeneous market of voluntary program participants, a focus on the programs' diffusion networks helps to explain their performance. This has implications for the design and implementation of such programs.