One hundred Spanish pig farms were surveyed to determine the biosecurity measures currently applied, as reported by farmers, and to investigate the importance awarded by farmers and veterinarians to each of these measures. Data was gathered by means of a questionnaire administered to farmers and veterinarians. Biosecurity measures were reported based on two scenarios: in the presence and in the absence of a highly contagious disease. Multiple-correspondence and two-step cluster analyses were performed to investigate the effect of farm type on the biosecurity level. Farmers awarded significantly higher scores to their farms' level of biosecurity than the veterinarians servicing said farms. According to the farmers and veterinarians, the most important biosecurity measures were those aimed at minimising the risk of disease introduction by visits and vehicles. Biosecurity practices seeking to reduce the risk of disease introduction by breeding stock were not applied on a considerable number of farms. The findings also revealed that medium-sized to large farms located in high pig density regions reported higher biosecurity measures than small herds located in low pig density areas. Copyright © 2012 Elsevier B.V. All rights reserved.