Ethical Consultancy

• Volans - "Focusing on the business of social innovation, Volans is part think-tank, part consultancy, part broker and part incubator. We are a for-profit company based in London and Singapore and we work globally with entrepreneurs, businesses, investors and governments to develop and scale innovative solutions to financial, social and environmental challenges." Their website has a blog to show the kind of projects they are involved with, and biographies of their employees.
• ?Whatif!: The Innovation Company - work with clients to increase their innovation capability. They run a 'Social Innovation Foundation' which uses the skills of the company (product and brand development, capacity building, etc) to assist social projects.

Consultancy for Charities and Non-profits

• Blackbaud - consultancy firm for over 22,000 charities and non-profits (based in the USA)
  
• Bridgespan Group -  the world leaders in advising charities and foundations on their strategy. For their top positions, the pay is reportedly as good as for commercial consultancies as well.
  
• Charity Consultants Ltd - a small fundraising consultancy for the non profit sector.
• Eastside Consulting - a small consultancy to social enterprises and charities. They offer a number of internships.
• New Philanthropy Capital - a think tank specializing in charities. Their website lists current vacancies and profiles of their current staff.
  

Development Consultancy

• MANGO - Management Accounting for non governmental organisations. Aims to help aid agencies and NGOs work more effectively.
• Practical Action Consulting - a commercial consultancy providing services to governments, NGOs, aid agencies, and the private sector. 

Environmental Consultancy

• Camco UK - Consultancy which aims to help combat climate change, through the development of new low carbon technologies and innovations. Continously recruiting people from technical, strategic or financial backgrounds.
• ENDS Directory - directory of environmental consultancy
• Environmental Resources Management (RCM) Consultants - a large environmental consultancy firm operating in UK, USA, and Asia. Clients include multinational corporations and governments.
• Impetus Consulting Ltd. – An environmental consultancy specialising in sustainable energy, waste minimisation and climate change.

Corporate Social Responsibility

Article 13 - experts in business responsibility, particularly corporate social responsibility, sustainability, and governance. Jobs are listed on their webpage, and they also offer internships (see the internships section for more details).

Future Considerations - a management consultancy firm which has a strong focus on corporate social responsibility, sustainability and carbon considerations. Works with UK and international corporations, local and national government, and charities.

Futerra Sustainability Communications - a communications agency which has only ever worked on corporate social responsibility and sustainability. Offices in London and New York. It provides a range of services to firms including PR, advertising, employee engagement, and strategy.

SustainAbility - a consultancy which specialises in sustainable development, and has an emerging economies programme. Their website contains biographies of current members of staff detailing their previous experience.

Many companies have their own CSR departments. For more information on careers in CSR a useful source is University of Edinburgh Careers Service.