Malaria remains a serious health concern across the globe. Historically neglected, non- human malarias were put back on the agenda by a paradigm shift in the fight against malaria from malaria control to malaria eradication. Here, we review the modeling of the relapsing parasites () and () in non-human primates with a specific focus on the contribution of these models to our current understanding of the factors that govern parasite-host interactions in and parasite biology and pathophysiology.