One of the criteria in evaluating a successful entrepreneur could be the extent to which anticipated expectations actually realises in performance. The expectations of decision makers are, apart from experience and knowledge, influenced by the quality of judgement. The perceptions of agricultural entrepreneurs on the various sources of uncertainty were investigated in the Wiens and Swartland (Southern and Western Cape). The expectations on product prices and yields of this sample of decision makers were observed and compared on two occasions. The heuristic of availability could be responsible for the relatively narrow probability distributions for the price of wheat, while some respondents showed bias in the form of conservatism.