Cocoa, diseases, especially the frosty pod rot, produced by the fungus Moniliophthora roreri (Cif.) Evans et al (Basidiomycetes, Marasmiaceae) are the main limiting factor of production in Latin America. This pathogen is aggressive and easily dispersed. Also, most commercial genotypes of cacao in the region are susceptible. The arrival of this pathogen to the Caribbean, Brazil and West Africa (largest producer area) can cause devastating effects in the global cocoa production. Combating moniliasis is difficult due to the time-consuming recommended practices. Moreover, there is currently insufficient information of the pathogen, thus it is essential to further study the basic aspects of the pathogen, the epidemiology of the disease and the climatic and production factors that affect the development of the epidemic, in order to achieve effective, simple and lasting control methods. The present investigation studied on the effect of macro and microclimatic factors such as precipitation, temperature and relative humidity as well as the production of cocoa on the initiation, development and impact of the moniliasis in the Atlantic Coast of Costa Rica. The research was divided into two parts. The first was an analysis of historical data (yield, climatic and phenological data) collected over 9 years by CATIE´s Cacao Breeding Program. The collection was utilized to generate regression trees from the accumulated data in order to rank the most relevant descriptors over the incidence of moniliasis in the different cacao clones over time. The second part was based on a field trial to study the microclimate (temperature, relative humidity and wetness) of each fruit and its correlation with the epidemiological development of the disease. While, two Campbell microclimate data loggers were placed on shade contrasting conditions. Also, a Burkard trap was also placed in the experimental area in order to quantify the amount of airborne spores present throughout the trial. The first pa