Objectives: The development of a new economic model for every single country that an intervention is used may be seen an inefficient. As such, model adaptation has often been proposed as a potential solution which could save scarce resources for decision makers in low and middle-income countries (LMICs). Using adjuvant treatment of early breast cancer as a case study, this study assessed the appropriateness of adapting an economic evaluation model originally developed in the UK for use in South Africa. The study aimed to determine the likely challenges that can arise from the routine adaptation of models to similar settings around the world. Methods: Eight model adaptation methods were identified from a systematic review and a citation search performed using Web of Science and Scopus databases. The eight methods were then appraised against criteria developed by the study team to select the most appropriate approach for LMICs. The Mullins checklist was formally applied in a case study assessing the cost-effectiveness of docetaxel and paclitaxel-containing chemotherapy regimens compared with standard treatments for adjuvant early breast cancer in South Africa. South African resource use patterns and unit cost data were obtained for estimating cost parameters, whilst targeted literature reviews were used to update the clinical effectiveness and utility data in the model. Results: Several methods are available to guide the process of adapting economic evaluation models for countries other than those in which they were conducted. The Mullins checklist seems the most appropriate approach for LMICs. We recommend that a consensus should be developed by a well-conducted Delphi panel. Conclusions: Based on model adaptation using resource use data from South Africa, the Mullins checklist appears to be an appropriate existing method to guide the transferability of economic evaluations done elsewhere to LMICs. However, research on refining the guidance further is urgently needed.