Thirty small, family-run dairy farms in which cows were housed in cubicle sheds were studied in order to determine the relationship between attitudes and personal characteristics of stockpeople, their interactions with cows, behaviour of cows during milking towards humans, and average milk yield. A questionnaire was given to the stockpeople to assess several components of the stockperson’s attitude (beliefs, emotions, and behavioural intentions) towards characteristics of cows and to behaviour towards cows. A self-report inventory assessed personal characteristics. The behaviour of stockpeople was strongly correlated with the behaviour of cows and moderately to milk yield. Cows avoided humans less if the stockpeople behaved more positively towards the cows in the milking parlour. The cows stepped/kicked more during milking and had a lower milk yield if the stockperson made moderate use of the hand, moderately loud vocalizations, and gentle use of a stick (neutral interactions). Attitudes and personal characteristics were found to be important determinants of stockperson-cow interactions and production success. Many stockperson attitude components were correlated to stockperson behaviour and to the cows’ milk yield. Personal characteristics were related to the attitudes and the behaviour of stockpeople. For example, stockpeople who were high on agreeableness used more positive interactions and less neutral ones, while pessimists were low on positive attitudes to cows. Conclusions stated that there was a strong influence of a stockperson’s attitude and personal characteristics on the behaviour of the stockperson and on the cow’s fear of humans, behaviour, and milk yield. Milk yield appears to be lower on farms where stockpeople have negative attitudes towards interacting with cows during milking and use more neutral behaviours. By initially identifying the main attitude components responsible for positive and negative behaviour, new measures of attitude and personal characteristics created were proven to be good predictors of stockperson behaviour. Use of such measures as predictors provides the possibility to improve human-animal interactions on small dairy farms by changing the relevant attitudes and behaviour of the stockpeople. Consequently, animal welfare and production may be improved.