Williams worked for Rem Koolhaas in Rotterdam and General Public Agency before setting up Common Office, an independent practice working with planning, politics, and the public. His writing has been published in journals and magazines including mono.kultur, Hunch, and Volume. Williams teaches ADS2 at the RCA with David Knight and Charles Holland, is External Supervisor for Spatial Practices at Central St Martins, and Specialist Urban Design Advisor to the Bartlett School of Architecture MArch Thesis programme. Among other roles Williams is vice-chair of the Tower Hamlets Design Review Panel. In 2014 he founded NOVUS, a thinktank for public sector planning. Finn is currently working on a new social enterprise to embed talented young designers within local authorities.