CallisonRTKLCallisonRTKL is a global architecture, planning and design firm formed from the October 2015 merger of Callison and RTKL Associates, both of which were subsidiaries of Arcadis NV.Chief Executive Officers (Effective Date) Kim Heartwell Kelly Farrell Tim Neal Lance K. Josal FAIAProjectsChapman Taylor and CallisonRTKL have submitted plans for the £1.4 billion redevelopment of Brent Cross Shopping Centre in North West London. CallisonRTKL designed the Four Seasons Residences in Beverly Grove, Los Angeles set for completion in 2019. Its 5th and Hill project at Pershing Square in Downtown L.A. features cantilevered, glass-bottomed swimming pools projecting from the building's envelope.