San Diego-based Graham Downes Architecture and Architectural Concepts Inc. have merged, and are now operating under the name Graham Downes Architecture.

Margit Whitlock, formerly principal of Architectural Concepts and now director of Graham Downes, said by phone April 20 that the two firms had competed and collaborated on projects for the past 18 years, and decided in January to combine into one company.

The merged firm, with a team of 20 designers and support personnel, is based at the Graham Downes Architecture office on National Avenue, in downtown San Diego’s East Village. It has satellite offices in Phoenix and Las Vegas.

Graham Downes’ recent design commissions include the Hard Rock Hotel in San Diego and The Padre Hotel in Bakersfield. The firm also designed the award-winning Tower23 Hotel in San Diego.

Whitlock’s former firm was the architectural designer of hospitality projects including Cibola Vista Resort & Spa in Arizona, the Island Empress in Florida and The Bond in Las Vegas.

Graham Downes Architecture was founded by international architect Graham Downes in 1994. The firm has done design work in the retail, hospitality, entertainment and multifamily residential industries.

— Lou Hirsh