IN 1995, THE municipality of Cartagena formed a joint venture with Aguas de Barcelona to provide water and sanitation services to the city. The new company, Aguas de Cartagena, signed a 26-year contract for operating and maintaining the services. This was the first private sector agreement in Colombia’s water and sanitation sector. In 1998, an additional contract was signed for the company to manage a major investment programme, mainly financed by international development banks. The case study indicates that the partnership has performed satisfactorily, particularly on the technical side, although progress in extending connections to low-income areas has been slow. However, the municipality lacks the capacity and inclination to negotiate effectively with the private partner and the process has not been very open (e.g., the performance targets presumably set out in the contract are not in the public domain). The author concludes that this is likely to limit the long-term potential for public-private partnership.