The Standard Treatment Guidelines (STG) and the National Essential Medicine List for Tanzania (NEMLIT) was first published in 1991. The fourth edition includes new sections on symptoms and syndrome. The STGs have been updated and are consistent with current national guidelines for diagnosis and management of common diseases. The guidelines also reflect changes in the management of various diseases including asthma and hypertension following recommendations from WHO and experts from international medical associations and agencies. There have been improvements in the format of treatment regimens, showing more clearly the classification of medicines by level of health care within the treatment guidelines, and not just in the NEMLIT.