Argentina and Costa Rica are two Latin American countries rich in natural attractions that make up most of their tourism attractiveness for visitors. However, Costa Rica has managed to establish itself as a successful example and leader in the Sustainable Tourism sector, while Argentina could not. The aim of the present work is to explore what can account for such differences: more specifically, why Argentina has been unable to establish healthy sustainable tourism development. To examine the research question, the present study sets to describe the Tourism Development Policy of Argentina and Costa Rica, analyse their sustainability, and compare both countries by using a comparative qualitative and interpretative case study method. Comparisons will be made concerning three different governance levels: international, national, and local. The results of the present study show a close resemblance of both countries’ international policy with a stark difference at the national level, with two main consequences. Firstly, it suggests a greater importance of the National Tourism Development guiding plan when it comes to setting directions of the sustainability of the sector. Secondly, the biggest contrast that can be identified between the two countries is found on the environmental component of sustainability. Thirdly, it is observed that the application of National Tourism Policy at a local level has a high impact on the sustainability of the touristic activity, especially in terms of the involvement and inclusion of local communities. Finally, suggestions and easily applicable modifications are formulated based on the Costa Rican example to improve the country’s tourism Development in the years to come.