(1) Background: In Southern countries, companies that employ a large number of workers are concerned with poverty reduction, which is the priority of their CSR policy. The banana sector has made great efforts to calculate a “living wage”, but this is not sufficient. How do we assess a decent living standard in Southern countries, where basic social needs are rarely covered by the public authorities? (2) Methods: the selection and analysis of the living standard assessment methods are based on a systematic review of the literature. (3) Results: We selected 427 references in total and classified them into 10 method families. Among them, we have not found a ready-to-use method. The paper therefore suggests an innovative methodology (CSDA) inspired by Townsend’s non-monetary deprivation score and by the importance of social norms and ties. Instead of using a list of goods to define a decent living standard, the new method relies on access to services proven to be important for public health by covering social needs. Moreover, this method is easy to implement for the private sector, highlights the priority social needs for workers on which the company can act with its CSR policy, and allows for cross-country comparison. (4) Conclusions: This last point is crucial for the producers’ commercial negotiations with large-scale distribution and also to prevent the flight of workers to other activities or competitors. With regard to poverty alleviation, it will depend on how the company uses the results of the CSDA assessment.