Grupa 5 Architekci is an architectural practice founded in Warsaw in 1998 by five architects: Roman Dziedziejko, Michał Leszczyński, Krzysztof Mycielski, Mikołaj Lech Kadłubowski, and Mariusz Jasiński. The firm arose during Poland’s post-communist transformation, quickly taking on major commissions despite limited early experience. Today, the studio employs about 40 architects with a practice shaped by a collective management structure and a focus on collaboration at all stages of design and investment.
Their portfolio covers a spectrum of project types, including residential quarters, office buildings, adaptive reuse of historic structures, schools, hospitals, and large public and transport facilities. In Warsaw, they have completed over 18 complexes of multifamily housing and a number of significant office projects, such as the headquarters of Millennium Bank and the recently completed Lakeside Offices near the Służewiecki Stream, a 43,771 m² modern office building recognized in 2024 by the European Property Awards for Office Architecture.
Notably, Grupa 5 Architekci also contributed to the renovation and modernization of the historic Main Railway Station in Wrocław. Their ongoing work includes the revitalization of historical tenements on Waliców Street in Warsaw, transforming sites marked by the city's wartime trauma into spaces for offices and public functions while preserving key historical remnants.
The firm’s design ethos can be described as human-focused, balancing modernist principles with contextual sensitivity and urban-scale thinking. Their work has earned multiple awards, demonstrating a commitment to both functional quality and architectural heritage.