Caseous lymphadenitis (CLA), caused by Corynebacterium pseudotuberculosis, is a significant cause of economic loss to the global sheep industries. Vaccination programs have been available in several countries for over 25 years and although declines in CLA prevalence have been recorded, the rate of decline may have been slower than expected due to poor compliance with manufacturer recommendations, particularly with booster vaccinations of lambs and annual vaccinations of adult sheep. Addressing CLA as a global economic and welfare problem for sheep producers and their industries requires evolution of best practice extension programs that ensure more efficient application of the available vaccines.