Patterns of bacterial infection have remained fairly static with Gram-positive bacteria predominating, although this varies between institutions and between patient populations, Similarly, antimicrobial resistance rates differ widely and reflect antibiotic use and exposure, Hence, each institution should devote microbiological resources to maintain surveillance and employ vigilance so that antimicrobial treatment protocols can be adapted to meet any new challenges, Most changes are being seen in the diagnosis of fungal infections, particularly aspergillosis, and the way in which it is being incorporated into treatment strategies, Curr Opin Infect Dis 13:337-342, (C) 2000 Lippincott Williams & Wilkins.