Enjoining (what is) right and forbidding (what is) evil (Arabic: ٱلْأَمْرْ بِٱلْمَعْرُوفْ وَٱلنَّهْيْ عَنِ ٱلْمُنْكَرْ, romanized: al-amr bi-l-maʿrūf wa-n-nahy ʿani-l-munkar) are two important duties imposed by God in Islam, as revealed in the Quran and hadith.

This expression is the base of the Islamic institution of hisbah (the individual or collective duty – depending on the Islamic school of law – to intervene and enforce Islamic law). It forms a central part of the Islamic doctrine for all Muslims. The injunctions also constitute two of the ten Ancillaries or Obligatory Acts of Twelver Shia Islam.

Pre-modern Islamic literature describes pious Muslims (usually scholars) taking action to forbid wrong by destroying forbidden objects, particularly liquor and musical instruments. In the contemporary Muslim world, various state or parastatal bodies (often with phrases like the "Promotion of Virtue and the Prevention of Vice" in their titles) have appeared in Iran, Saudi Arabia, Nigeria, Sudan, Malaysia, etc., at various times and with various levels of power.