Although the personality of the manager has been shown to predict performance in many fields, in agriculture, this relationship has not been studied in detail. In the study presented here, 59 dairy farm managers in England andWales completed psychological assessments; on 40 of 53 measures, farmers were found to be distinct from the general working population norm. Significant correlations to farm profitability for four of the 53 measures were found. Almost 40% of the variation in farm profitability was predicted by a simple linear model with just three of these personality measures: ‘Detail Conscious’ and ‘Leadership’ measures positively and, ‘Relaxed’, negatively, predicted farm profitability. Though observational, and not demonstrating cause and effect, the associations are strong. These three measures are, thus, candidate variables for personality measures that drive farmer and farm manager performance. Longitudinal, or intervention studies, may demonstrate causality in the future. In the interim, being cognisant of these attributes during the hiring and training of farm staff, particularly those with management roles, may well result in improvements in farm profitability.