Alleen Siu – Associate Partner

Alleen is an Associate Director with over 20 years’ experience across the UK, Europe, US and Asia, delivering complex mixed-use, residential and heritage-led projects.

She joined the practice as part of the NEO Bankside team, contributing to the award-winning residential development adjacent to Tate Modern. Her role focused on high-quality apartment interiors, alongside the design and delivery of a five-storey mixed-use building and bespoke garden pavilion. The project was shortlisted for the RIBA Stirling Prize in 2015.

From 2012–2017, Alleen was Project Architect for Burlington Gate, a mixed-use gallery and residential scheme in Mayfair. Working closely with client, consultant and contractor teams across all stages, she played a key role in delivering the development, including the area’s first new public arcade since the 1930s.

Following this, she led and contributed to a range of competition bids and feasibility studies, strengthening strategic design and early-stage delivery expertise.

Alleen is currently working on the extension to the Grade I listed British Library, delivering new public, education and exhibition spaces, alongside a life science hub and integration with future Crossrail 2 infrastructure.

She is also Project Lead for Bromley-by-Bow, a major regeneration scheme centred on a unique collection of Victorian gasholders. This mixed-use masterplan delivers around 2,000 homes, community and commercial space, and significant public realm, including a new riverside park. The project combines heritage reuse, circular economy principles and ambitious sustainability targets, creating a distinctive and inclusive place for local communities.