Although many control practices to improve the mastitis situation on a farm and to reduce the economic losses of mastitis are available, the adoption rate and level of compliance of these measures are generally low. Implementing new measures involves costs, which can be divided into costs for the milking parlour and other issues. These costs were subdivided into long term investments, short term investments, labour, and change of routines. In traditional cost-benefit analyses all costs belonging to the different factors are set on a comparable monetary value. Although in an economic way this is correct, farmers may value some costs in a different way because of certain preferences, influencing the adoption rate of the mastitis reducing measures. The objectives of this study were to explore differences between preferences of cost factors according to Dutch dairy farmers, and to distinguish different groups of farmers accordingly. 136 farmers were questioned by adaptive conjoint analysis about their individual preferences. A large difference between these preferences was found. Taking individual preferences together, overall, long term investments in issues other than milking parlour were preferred most and changing routines in issues other than milking parlour were preferred least. The results of this study show that, given the large variation in the valuations, to improve the adoption rate of management measures it is important to take the preference of cost factors into account in advice given.