Philip Masters BSc MA, PhD, Dip LA, CMLI is director of ACTA. He trained in biology and landscape architecture before studying history at the Centre for English Local History at the University of Leicester and worked in the public sector and for landscape and environmental consultancies before starting acta. During that time he worked on projects ranging from major infrastructure such as the A27 Brighton Bypass to heritage projects such as the management plan for Avebury World Heritage Site. He is directly responsible for all of the acta projects described on this site and is an experienced project manager and expert witness.

Matt Jackson MCIHort is an independent landscape consultant specialising in the restoration, development and ongoing management of heritage gardens and landscapes. Following a long career with the National Trust including Stourhead, Scotney Castle and Sissinghurst, with the University of Oxford and private clients he is now an associated consultant with ACTA.

Clive Mayhew BA, MICFor, MArborA, CEnv is an associate consultant. He has over 20 years of experience of arboriculture in the private sector and in local authorities. His technical knowledge - along with a broad understanding of the planning process - means that he brings an informed, practical and pragmatic approach to any project. He has a particular interest in the design challenges presented by the retention and incorporation of historic trees into new developments and in sustainable land management.

Amanda Davey BSc BA DipLA is the associate consultant who deals with graphics and GIS. She is a geographer and landscape architect and her career as a consultant has followed work in museums and archaeology, as well as map curator at The University of Sussex. Fourteen years working for a landscape consultancy on a mixture of large infrastructure schemes, roads, historic parks and also World Heritage Sites helped to increase the diversity of her experience. In 2004 Amanda set up Tilia Services which works closely with acta on many projects including historic parks and gardens and Cold War site conservation plans.