Dowgierd joins as a group director, and reports to Grand Union's founder Matt Nicholls.
He joined Greenroom in October 2005 to work on developing its branded content business. Before that he was a founder of Happen, the planning arm of Fallon.
Dowgierd helped devise the business plan for Happen when he was an account director at Fallon, but only stayed with the division for a year, before leaving without another job to go to. A month after his departure, he joined Greenroom.
Online plans for Boots this year include launching dedicated product websites for the No 7 cosmetics range and for the Boots Expert brand, which is designed to deal with minor health and beauty niggles such as dry skin or hair removal.
Grand Union is also looking at redeveloping the boots.com website in order to bring it into the Web 2.0 era. The agency aims to make it one of the best in class for retail websites in the world.
Grand Union was appointed by the high-street retailer in October 2006 to develop a digital strategy. Boots previously worked with the "Los Galacticos" consortium of agencies, led by Mother, to handle integrated communications.
Other Grand Union clients include npower and Energy Savings Trust. It also works on a COI brief to promote safer sex.