In the period 2002 to 2006 a total of 94 beef suckler herds submitted faecal samples to the Central Veterinary Research Laboratory, which yielded a culture positive result for Mycobacteriumavium subspecies paratuberculosis (MAP). The composition of these herds and movement in to and out of them during this five-year period is analysed. These findings are compared with those from a control group of 243 suckler herds which gave ELISA negative results as part of a survey which was conducted to estimate the prevalence of paratuberculosis (Johne's disease) in the Irish cattle population. Analysis of the data showed that infected herds were significantly larger than non-infected herds but that there was no significant difference in movements in or out of the herds in the two groups. In the infected herds a large percentage were sold on to other herds rather than going directly to slaughter. In the control herds there were very few closed herds, those that did not buy in any animals. These two points would need to be addressed in herds establishing a control programme for the disease.