Santiago joined Montgomery Sisam in 1990, becoming a Principal in 2001. Uniquely experienced in delivering a full range of architectural services, including master planning, feasibility studies, urban redevelopment initiatives as well as complex expansion and renewal projects, Santiago works across many industry sectors, successfully engaging in and contributing to all phases of project development.

Building strong, ongoing working relationships with leading service providers Extendicare, Chartwell REIT, Revera Living and Sienna Seniors Living, Santiago has designed and delivered over 1 million square feet of seniors housing that spans the spectrum of care. Working diligently to establish priorities and align interests, Santiago assists his Clients in gaining functionally efficient, operationally sustainable, purpose-built spaces that successfully meet ever more stringent Ministry requirements.

Further to his work in seniors housing, Santiago has developed innovative and ground-breaking solutions for the George Street Redevelopment, the Toronto Grace Healthcare Centre Infrastructural Renewal, the St. Thomas Elgin General Redevelopment, and the Toronto and Region Conservation Authority Restoration Services Centre, the first building in Eastern Canada to be LEED Platinum Certified. These projects demonstrate his commitment to delivering client vision within strict budget, schedule and regulatory parameters.

A steward for the design of healthy buildings and healthy communities, Santiago promotes an integrated design process focused on simple, low-cost design solutions that drive high performance sustainability outcomes. He has authored a number of studies for the MOHLTC examining the implementation of LEED initiatives and sustainable design strategies respectively in long term care homes. He is also a frequent speaker on issues of sustainable building and has been named a delegate to the World Green Building Council.

Deeply invested in promoting excellence in urban planning and design, Santiago is a former member of the Vaughan Design Review Panel, a non-statutory advisory body of professionals advising City staff on matters of design that affect the public realm and fabric of the city.