In the recent past the coffee production sector witnessed a rapid expansion of
certification programs promoting voluntary sustainability standards, one of which is
UTZ Certified. In this article we assess the impact that this program has on
participating smallholder farmers by reviewing the results of an agent-based
simulation for modeling rural producer organizations. We present the developed
empirical simulation model by sharing the common protocol, which documents the
structure the applied simulation tool and its parameterization for the group of coffee
farmers, and reporting the results of model validation. The main strength of this
assessment is that it considers certification-related costs of the farmers, which are
ignored in the analyses available so far. The obtained simulation results constitute
quantitative evidence of UTZ certification being able to create considerable positive
impacts on the participating farmers. The results outline the importance of external
financing and supportive measures complementing certification in groups.