Medicines play a crucial role in the prevention and treatment of diseases. When used correctly, they can offer simple and cost-effective solutions to many health problems. Today many people have little or no access to safe and effective drug therapies and may be at risk of serious health problems due to treatment with ineffective, poor quality products, or incorrect and irrational use of medicines.

Formularies can be useful tools in solving some of these problems of drug therapy as they can:

- provide impartial drug information to counteract biased promotional activities or fill the gap where access to accurate, and up-to-date information is limited;

- promote the appropriate use of safe, effective and good quality medicines;

- help in the elimination of unsafe, ineffective or poor quality medicinal products by identifying effective and safe medications; and

- support cost-effective utilization of drug budgets and improve access to essential medicines.