Specific restrictions placed on the warring party in the preparation of an attack.   An attack must be cancelled if it becomes apparent that it is of a type that is prohibited. If circumstances permit, an advance warning must be given for those attacks which may affect the civilian population. In determining the objective of an attack, and when a choice is possible, the one causing least danger to the civilian population must be selected. Furthermore, IHL requires those planning and deciding on an attack to take precautionary measures, including refraining from attacking when incidental loss of civilian life or destruction of civilian objects outweighs the military advantage of the attack.   The meaning of these obligations in practice remains controversial in many cases, mainly with regard to which precautions are “feasible”. Military and humanitarian considerations may influence the feasibility of such precautions: the importance and the urgency of destroying a target; the range, accuracy and effects radius of available weapons; the conditions affecting the accuracy of targeting; the proximity of civilians and civilian objects; the possible release of hazardous substances; the protection of the party’s own forces (and the proportionality between the additional protection for those forces and the additional risks for civilians and civilian objects when a certain means or method is chosen); the availability and feasibility of alternatives; the necessity to keep certain weapons available for future attacks on targets which are militarily more important or more risky for the civilian population. See also Conduct of hostilitiesPrecautions against the effect of attacks;




    PI, 57

    CIHL, 15-21

- an attack must be cancelled if it becomes apparent that it is a prohibited one

    PI, 57/2b 

    CIHL, 19

- advance warning must be given, unless circumstances do not permit

    PI, 57/2c

    CIHL, 20

- when a choice is possible, the objective causing the least danger to the civilian population must be selected

    PI, 57/3

    CIHL, 21

- additional obligations of those who plan or decide upon an attack: verify that objectives are not illicit, choose means and methods avoiding or minimizing civilian losses, refrain from attacks causing disproportionate civilian losses

    PI, 57/2a

    CIHL, 16-17



ICRC, The Challenges of Contemporary Armed Conflicts

Israel, Operation Cast Lead (Part I, Paras. 132-133, Part II, Para. 529)

Israel, Human Rights Committee’s Report on Beit Hanoun (Paras. 26 and 38-42)

Israel, Report of the Winograd Commission (Para. 26)

Case Study, Armed Conflicts in the former Yugoslavia (Para. 27)

Human Rights Committee, Guerrero v. Colombia

Afghanistan, Goatherd Saved from Attack

ECHR, Isayeva v. Russia

ECHR, Khatsiyeva v. Russia (Paras. 21 and 139)

Georgia/Russia, Human Rights Watch’s Report on the Conflict in South Ossetia (Paras. 18-25)

Georgia/Russia, Independent International Fact-Finding Mission on the Conflict in South Ossetia (Paras. 66-67, 74-82)

Cambodia/Thailand, Border Conflict around the Temple of Preah Vihear

Iran, Victim of Cyber warfare

The armed conflict in Syria

Israel, Blockade of Gaza and the Flotilla Incident

Libya, NATO Intervention 2011

UN, Report of the Secretary-General for the World Humanitarian Summit

Afghanistan, Attack on Kunduz Trauma Centre

ICRC, International Humanitarian Law and the challenges of contemporary armed conflicts in 2015 (Paras. 155160178-180, 257-258)

Israel/Palestine, Operation Protective Edge (Gaza, 13 June - 26 August 2014)

Sri Lanka, Naval War against Tamil Tigers

Syria, Report by UN Commission of Inquiry (March 2017)

Afghanistan, Bombing of a Civilian Truck

Italy, Use of force against ambulances in Iraq

Syria, the Battle for Aleppo

Iraq/Syria/UK, Drone Operations against ISIS

ICRC, Statement - War in Cities ; What is at Stake?

Germany, Aerial Drone Attack in Mir Ali/Pakistan

Central African Republic, No Class: When Armed Groups Use Schools

Syria: Attacks on Oil Infrastructure

Somalia/US, Airstrikes in Somalia 

The Netherlands, Fighting in the Chora District (Afghanistan) 

United States, The US Plan to Mitigate Civilian Harm in Armed Conflicts


Suggested readings:

DESGAGNÉ Richard, “The Prevention of Environmental Damage in Time of Armed Conflict: Proportionality and Precautionary Measures”, in YIHL, Vol. 3, 2000, pp. 109-129.   HENDERSON Ian, The Contemporary Law of Targeting: [Military Objectives, Proportionality and Precautions in Attack under Additional Protocol I], Leiden, Boston, M. Nijhoff, 2009, 266 pp.