An evaluationofthe present system of testing of advanced wheat lines was made in terms of expected genetic gain from selection. Indications are that this system can function quite effectively if properly managed. The feasibility of substituting high potential test sites for low potential test sites in order to facilitate yield testing was also investigated. It was concluded that it may be more appropriate to select test sites on the basis of production intensities, predominant soil types and annual rainfalls. One such solution was derived and is proposed for implementation in the Winter Rainfall Region.S. Afr. J, Plant Soil1984, 2: 135−140