The acceleration of sanitation delivery towards meeting the South African Government's target of completely eradicating the existing backlogs by 2010, has led to a surge of activities. As part of its strategy for ensuring that basic sanitation is provided, the policy has recommended that a ventilated improved pit latrine (VIP) is considered as the basic minimum requirement in the form of a sanitation technology. The up-scaling and delivering of sanitation in many cases in the form of VIPs and its derivatives, as well as urine diversion technology are beginning to pose many technical challenges. The principles on which they have been designed are not always being observed in practice. As a result, some systems are filling up much faster than expected. Research has found that the breakdown in the faeces is not happening as would be expected in an anaerobic reactor, and that the drying of faeces in humid conditions, even with the use of drying agents, is not optimum. These problems, which are being experienced in the field, will have long term repercussions on the sustainability of sanitation provision. This paper aims to share these experiences and findings of research, and the impact it may have on the Sanitation MDG goals.