A heat-intolerance (HI) syndrome in cattle in Tanzania was suspected to be associated with previous, clinical foot-and-mouth disease (FMD). A participatory appraisal (PA) method called "matrix scoring" was used to explore livestock-keeper perceptions of association between HI and cattle diseases. A PA method called 'proportional piling' was used to estimate herd incidence of FMD and other diseases, herd incidence of HI, and association between HI and other cattle diseases. Use of matrix scoring and proportional piling with pastoral Maasai informants demonstrated association between FMD and HI. With agropastoral Sukuma informants, the matrix-scoring method did not indicate an association between FMD and HI, whereas the proportional piling method indicated a weak association. Results were supported by calculation of positive predictive values for herder diagnosis of HI and FMD. Clinical examination of cattle by veterinarians was used to confirm HI cases and detection of antibody to non-structural proteins of FMD virus was used to confirm previous clinical FMD.