After leaving college, Lymbery volunteered for several months at an RSPB reserve in Titchwell Marsh, Norfolk. From 1996 to 2005 he led birdwatching tours with a holiday company called Gullivers Natural History Holidays, travelling to locations including Costa Rica, Seychelles, the United States and the Spanish Pyrenees. As Campaigns Officer and later, Campaigns Director at Compassion in World Farming from 1990 to 2000, he campaigned to end the live export of farm animals and ban the barren battery cage in the EU. He worked as Communications Director at the World Society for the Protection of Animals (Now known as World Animal Protection) from 2003 to 2005. In 2005, Lymbery became chief executive officer of Compassion in World Farming. Under his leadership the charity has been awarded the Observer Ethical Award for Campaigner of the Year and BBC Radio 4 Food and Farming award for Best Campaigner and Educator.
Published by Bloomsbury in January 2014, Lymbery's book Farmageddon: The True Cost of Cheap Meat is described as 'a wake-up call to change our current food production and eating practices, looking behind the closed doors of the runaway industry and striving to find a better farming future.' Joanna Lumley says of this book, "A devastating indictment of cheap meat and factory farming. Don't turn away: it demands reading and deserves the widest possible audience.”
- Lymbery, Philip and Isabel Oakeshott (2014-01-31). Farmageddon: The True Cost of Cheap Meat. London: Bloomsbury. ISBN 978-1-40884-644-5.
- Lymbery, Philip (2008-03-30). "The Theory and Application of Welfare Potential", in Proceedings of the Importance of Farm Animal Welfare Science to Sustainable Agriculture Forum. Beijing: CIWF, RSPCA, WSPA, HSI with the support of the European Commission.
- Lymbery, Philip (2004). “A Comparison between Slaughterhouse Standards and Methods Used during Whaling”, “An Introduction into Animal Welfare”, in Philippa Brakes, Andrew Butterworth, Mark Simmons & Philip Lymbery, Troubled Waters – A Review of the Welfare Implications of Modern Whaling Activities. London: WSPA. ISBN 0-9547065-0-1.
- Druce, C. & Philip Lymbery (2003). Outlawed in Europe: Farm Animal Welfare – 3 Decades of Progress in Europe. New York City: Animal Rights International.
- Lymbery, Philip (2002). Laid Bare: The Case Against Enriched Cages in Europe. Petersfield: CIWF.
- Lymbery, Philip (2002). Farm Assurance Schemes & Animal Welfare: Can We Trust Them? Petersfield: CIWF.
- Lymbery, Philip (2002). Supermarkets & Farm Animal Welfare: Raising the Standard. Petersfield: CIWF.
- Lymbery, Philip (2002). In Too Deep: The Welfare of Intensively Farmed Fish. Petersfield: CIWF.
- Lymbery, Philip & Jacky Turner (1999). Brittle Bones: Osteoporosis & the Battery Cage. Petersfield: CIWF.
- Lymbery, Philip (1992). The Welfare of Farmed Fish. Petersfield: CIWF.
- Lucy Siegle, "Have vets really sold out to industrial agri-business?", The Observer. 19 January 2014. Retrieved 27 January 2014.
- Isabel Oakeshott, "Goodbye birds. Goodbye butterflies. Hello... farmageddon", Sunday Times. 19 January 2014. Retrieved 27 January 2014.
- "Gateway to Farm Animal Welfare", Food and Agriculture Organization of the United Nations. Retrieved 27 January 2014.
- "About Philip", PhilipLymbery.com. Retrieved 16 January 2014.
- Tristram Stuart, Farmageddon: The True Cost of Cheap Meat: Review, The Guardian, 29 January 2014.
- "Council Members", Sustain. Retrieved 16 January 2014.
- Graham Willgoss, "Focus: People Management – The big appointment – Lymbery back as World Farming chief", Third Sector, 31 August 2005. Retrieved 16 January 2014.
- "Philip Lymbery: Farmageddon: The True Cost of Cheap Meat", Oxford Literary Festival. Retrieved 27 January 2014.
- "Meet the Author: Philip Lymbery", BBC Wildlife Magazine, March 2014.
- "Farming Today: 21/01/04". January, 2014. BBC. Retrieved 28 January 2014.
- "Farmageddon", Guardian Bookshop. Retrieved 27 January 2014.
- Joanna Lumley, "Farmageddon: The True Cost of Cheap Meat", Amazon UK. Retrieved 16 January 2014.