This presentation describes a process of Participatory Technology Development that took place in the Teso Farming System (TFS), northeast Uganda between 1998 and 2004. The main objective of the research/extension was to alleviate labour constraints and drudgery associated with weeding annual crops (in an area where the presence of HIV is reducing the numbers of economically active people available for agricultural labour) and to reduce costs and improve returns to these enterprises. There has been a shortage of draught animals in the TFS following civil disruption during the 1980s and 1990s. This constraint has been addressed by a number of ‘restocking’ projects and many households are now able to open up land (plough) with oxen. The benefits of using draught animal power (DAP) however, are not fully realised until animals are used for weeding and other tasks (planting, groundnut lifting and potato ridging). Although only 50% of households own oxen, 90% use them for ploughing, including some of the poorest households as it is cheaper to hire oxen than to employ manual labour. Hand weeding is mainly undertaken by women and children resulting in drudgery, withdrawal of children from school during the weeding seasons, high costs if labour is hired to undertake the task, reduced yields (in poorly weeded fields) and poor returns (gross margins).