Some information on NGOs with policy and advocacy internships / careers

Hello,

Can we gather a list of London-based NGOs whose websites are worth checking for information on policy and advocacy positions ? Based on my own research and the presence on these websites, at present (5/9/14), of policy/advocacy positions, I offer the following for starters:

Human Rights Watch
http://www.hrw.org/

World Development Movement
http://www.wdm.org.uk

One
http://www.one.org

Overseas Development Institute
http://www.odi.org

Save The Children
http://www.savethechildren.org.uk

Oxfam
http://www.oxfam.org.uk

Wellcome Trust
http://www.wellcome.ac.uk

Anti Slavery International
http://www.antislavery.org

Article 19
http://www.article19.org

Child Rights International Network
http://www.crin.org

Your contributions to this thread will be of great assistance to myself and many other graduates. Thank you!