Campaigners argue against the proliferation of weapons in poor countries and areas of political instability or conflict. In recent years there has been considerable public outcry over weapons considered to disproportionately harm civilians such as landmines and cluster bombs as well as over arms exports to oppressive regimes. Often these weapons have originated from western democracies.

Many also disapprove of what they regard as the harmful diversion of government funds from social spending to unproductive and destructive military programmes, both in developed and developing countries. For some, including pacifists and some religious groups, the use of military force is unacceptable whether for defensive or offensive purposes.

It is possible to screen out companies involved in military production or sale. The exact criteria used for negative screens can vary. Considerations include:

• the nature of products or services sold to the military (whether this includes civilian products or services, such as non combat clothing, accommodation and office facilities)
• whether the company’s products or services constitute all or part of a weapons system or a nuclear weapons system
• what international military sales activities the company is involved in
• the proportion of turnover received from military sales