Tilly established IES Consulting in 2009. During the course of her career she has worked for Northamptonshire County Council as a Biodiversity Action Plan officer, set up Nature Improvement Areas for Natural England, had a secondment to Defra and worked for both a small ecological consultancy and then a multi-national engineering consultancy in their ecology team. Tilly has a Biology degree from the University of Bristol, and an MSc in Restoration Ecology of Terrestrial and Aquatic Environments from the University of Liverpool.
Vilas joined IES Consulting as a Director in 2015. After finishing the training programme run by Somerset Environmental Records Centre, he has variously worked for ecological consultancies, a multi-national engineering consultancy and as a County Ecologist for Monmouthshire Council.