Healthcare professionals are widely exposed to large numbers and varieties of microorganisms. Human immunodeficiency virus (HIV) and other blood-borne contagious infections have increased the need to protect both women and midwives from infection. The term ‘standard precautions’ (previously having incorporated ‘universal precautions’) refers to the measures taken universally, i.e. by all health professionals for all women and babies, all the time, (whatever the clinical environment) to achieve mutual protection. As an important area of care, the reader is required to keep up to date with developing protocols, both for self-protection and to provide the best possible care. The ‘cost’ of infection to individuals (service users and staff), the NHS and the community as a whole is large and the increasing incidence of healthcare-acquired infections (HCAIs) all mean that complacency cannot be permitted. This chapter reviews the use of standard precautions and the principles of isolation nursing.