Vickery Holman is hosting the event to offer guidance on ensuring best value with development projects.
Anthony Eke, head of land and planning, said: "The economic downturn coupled with complex legislation has really affected both the public and private sector development market.
"Added to this we're now starting to see a number of development sites with planning consent that are no longer viable.
"It can be worrying for both the public and private sector. But there are opportunities for successful and efficient outcomes and we aim to show that during this open day."
The open day takes place at the firm's Exeter office in Southernhay Gardens on Friday, February 13, from 10am to 4pm.
For more information or to reserve a place, call Mr Eke on 01752 273834.