En paises con grandes problemas de saneamiento y pocos recursos, como los que estan en vias de desarrollo, se requieren plantas de tratamiento de aguas residuales domesticas –PTARD– apropiadas y sostenibles; dado que estos paises se localizan en general en regiones de clima tropical y subtropical (temperaturas superiores a 20 oC), la digestion anaerobia es una tecnologia clave que genera subproductos con valor agregado (bioenergia, nutrientes y agua para reuso). America Latina es la region con mayor numero de PTARD anaerobias, siendo el reactor UASB el de mayor aplicacion para el tratamiento del ARD; su implementacion a escala tan grande como la de la PTARD Onca (Belo Horizonte, Brasil) demuestra que es una tecnologia consolidada, con eficiencias de reduccion entre 65 % y 80 % de DQO y TRH entre 6 y 10 horas. Sin embargo, es necesario continuar avanzando en el mejoramiento y perfeccionamiento de los actuales metodos de tratamiento que permitan soluciones tecnologicas respetuosas con el ambiente y adecuadas a las condiciones socioeconomicas y culturales propias de cada region. Este documento plantea un analisis y reflexion sobre el tratamiento anaerobio de ARD en paises en desarrollo y sobre las perspectivas de aplicacion en pequena y gran escala. Keywords: Appropriate and sustainable municipal wastewater treatments plants –WWTP– are strongly required in developing countries which face both sanitation problems and poverty. Anaerobic digestion, as a leading technology that generates value added products (i.e. bio-energy, nutrients and water for reuse) has proved to be suitable in those countries, which are mostly placed in tropical and subtropical regions with temperatures higher than 20 oC. Latin America is the region with the highest number of anaerobic WWTP, being the UASB reactor the most common technology for municipal wastewater treatment. Onca WWTP (Belo Horizonte, Brazil) is an example of a large scale implementation, showing that UASB is a stabilized technology with COD removal efficiencies ranging from 65 % to 80 % and HRT between 6-10 hours. However, further research is highly needed in order to improve and upgrade the existing treatment methods; so as to achieve technological solutions that prove to be environmentally harmless and suitable to each particular socio-economic and cultural condition. This work is aimed at analyzing and discussing the anaerobic treatment of domestic wastewater issues and its application perspectives at both small and large scale in developing countries.