3XN

3XN is a Danish architectural practice headquartered in Copenhagen, with offices in Stockholm, London, New York, and Sydney. The practice was founded in Aarhus in 1986 by Kim Herforth Nielsen, Hans Peter Svendler Nielsen, and Lars Frank Nielsen under the name Nielsen, Nielsen & Nielsen, later shortened to 3 X Nielsen and then 3XN. Its work spans architecture, urban development, interior environments, research, and design for cultural, educational, civic, commercial, residential, sports, hospitality, healthcare, and infrastructure projects. The firm’s stated design approach connects architectural form with the way people use and experience buildings. Its projects commonly emphasize social interaction, public accessibility, strong spatial identity, and the relationship between buildings and their urban context. The practice also presents sustainability and technological experimentation as important parts of its work, rather than treating them as separate technical exercises. This orientation has enabled 3XN to work on both highly public cultural buildings and complex commercial or institutional developments. 3XN’s early international profile developed through competition successes and commissions outside Denmark. The Muziekgebouw concert hall in Amsterdam, for which the practice won a competition in 1997, became an important international reference and was completed in 2005. The Danish Embassy in Berlin, completed in 1999, further established the firm’s ability to work on significant public and diplomatic architecture. Other international projects have included the Museum of Liverpool, Olympic House for the International Olympic Committee in Lausanne, cube berlin, Quay Quarter Tower in Sydney, and projects in Sweden, Norway, the Netherlands, Belgium, Canada, France, the United Kingdom, and Australia. In Denmark, the firm is associated with projects such as Ørestad Gymnasium, the Tivoli Concert Hall extension, Alsion in Sønderborg, Hotel Bella Sky, UN City, Denmark’s National Aquarium—The Blue Planet—and Royal Arena. These projects demonstrate the breadth of its practice, from education and research to hospitality, marine science, diplomacy, corporate headquarters, and large-scale public assembly. In 2007, 3XN established GXN, a research and development department focused on new materials, environmental technologies, circular design, and innovation. GXN has worked on material experimentation and product design, including lamps, and developed the Louisiana Pavilion, a biocomposite structure presented at the Louisiana Museum of Modern Art during the COP15 climate conference. GXN has also collaborated with Cradle to Cradle Denmark on principles for more circular building practice. 3XN remains a privately held, internationally active architecture practice. Kim Herforth Nielsen serves as Creative Director, while the firm is described as being managed by a senior partner group. Publicly available reference material does not establish a complete list of the current partners, ownership structure, employee count, revenue, or financial performance.

3XN was established in Aarhus, Denmark, in 1986 by Kim Herforth Nielsen, Hans Peter Svendler Nielsen, and Lars Frank Nielsen. The original name, Nielsen, Nielsen & Nielsen, was later adapted to 3 X Nielsen and ultimately 3XN. From the beginning, the practice sought to combine a clear theoretical basis with buildings that had a strong material and visual presence. Its work developed across public, cultural, educational, commercial, and residential commissions. The founding partnership changed over time. Hans Peter Svendler Nielsen left the firm in 1992, and Lars Frank Nielsen left in 2001. Kim Herforth Nielsen continued as the practice’s most publicly identified creative leader. The firm is described as being led by a senior partner group, although the available reference material does not provide a complete current membership list. A major stage in 3XN’s international development came through the Muziekgebouw concert hall competition in Amsterdam, won in 1997. The building was completed in 2005 and received several architectural awards. The Danish Embassy in Berlin, completed in 1999, was another important international commission. These projects helped establish a broader portfolio beyond Denmark and were followed by work in Europe, North America, Asia, and Australia. The practice’s Danish portfolio includes the Tivoli Concert Hall extension, Ørestad Gymnasium, Alsion university and concert complex in Sønderborg, Hotel Bella Sky, UN City, The Blue Planet national aquarium, Royal Arena, and the Lighthouse development in Aarhus. Internationally recognized projects include the Museum of Liverpool, Olympic House in Lausanne, cube berlin, and Quay Quarter Tower in Sydney. The firm has also designed headquarters, aquatic facilities, cultural centers, schools, hospitals, housing, hotels, and mixed-use developments. In 2007, 3XN founded GXN as a dedicated research and development unit. GXN investigates new materials, green technologies, circular construction, and ways to integrate research into architectural practice. It has also developed design products such as lamps. One notable research-oriented project was the Louisiana Pavilion, a biocomposite pavilion displayed at the Louisiana Museum of Modern Art during the COP15 climate conference. GXN has collaborated with Cradle to Cradle Denmark on the development of a Danish building manual based on circular-design principles. By the 2010s and 2020s, 3XN had become an international practice with offices in Copenhagen, Stockholm, London, New York, and Sydney. Its completed and ongoing portfolio includes major projects in the United Kingdom, Sweden, Germany, Australia, Canada, France, Switzerland, China, South Korea, and other markets. The available sources confirm the firm’s projects, awards, and broad design direction, but do not provide reliable public information about revenue, ownership, staffing levels, or a complete corporate timeline.

• 2022

  Quay Quarter Tower completed

  [1]3XNen.wikipedia.org

  3XN completes the major Quay Quarter Tower project in Sydney.

• 2020

  cube berlin completed

  [1]3XNen.wikipedia.org

  The cube berlin office building is completed in Germany.

• 2019

  Olympic House completed

  [1]3XNen.wikipedia.org

  3XN completes the International Olympic Committee headquarters in Lausanne.

• 2013

  The Blue Planet and UN City completed

  [1]3XNen.wikipedia.org

  Two major Copenhagen projects, Denmark’s National Aquarium and UN City, are completed.

• 2007

  GXN research department established

  [1]3XNen.wikipedia.org

  3XN creates GXN to develop research in sustainable materials, technology, and circular construction.

• 2001

  Lars Frank Nielsen leaves the practice

  [1]3XNen.wikipedia.org

  The last of the two original partners other than Kim Herforth Nielsen leaves 3XN.

• 1999

  Danish Embassy in Berlin completed

  [1]3XNen.wikipedia.org

  The practice completes the Danish Embassy in Berlin.

• 1997

  Muziekgebouw competition won

  [1]3XNen.wikipedia.org

  3XN wins the competition for the Muziekgebouw concert hall in Amsterdam, an important step in its international development.

• 1992

  Hans Peter Svendler Nielsen leaves the practice

  [1]3XNen.wikipedia.org

  One of the three founding partners departs the firm.

• 1986

  Practice founded in Aarhus

  [1]3XNen.wikipedia.org

  Kim Herforth Nielsen, Hans Peter Svendler Nielsen, and Lars Frank Nielsen establish Nielsen, Nielsen & Nielsen, the practice that later becomes 3XN.

An international architecture practice focused on human experience, social interaction, contextual design, innovation, and sustainability.

• Concert hall · 2005

  Muziekgebouw

  A concert hall in Amsterdam that followed 3XN’s 1997 competition victory and was completed in 2005. The project helped establish the practice internationally and received multiple architecture and urban-development awards.

• Museum · 2011

  Museum of Liverpool

  A major cultural building in Liverpool completed in 2011. It expanded 3XN’s international cultural portfolio and demonstrates the practice’s approach to creating publicly accessible architecture with a strong civic presence.

• Aquarium · 2013

  The Blue Planet

  Denmark’s National Aquarium in Copenhagen, completed in 2013. The project combines a prominent sculptural exterior with visitor-focused circulation and exhibition spaces dedicated to aquatic life.

• Institutional headquarters · 2019

  Olympic House

  The headquarters of the International Olympic Committee in Lausanne, Switzerland, completed in 2019. It is one of 3XN’s most significant institutional projects and reflects the practice’s interest in collaborative workplaces and sustainability.

• Office building · 2020

  cube berlin

  A Berlin office building completed in 2020. The project is among 3XN’s prominent European workplace commissions and forms part of the firm’s broader work on technologically advanced and socially interactive commercial environments.

• Commercial high-rise · 2022

  Quay Quarter Tower

  A major Sydney office-tower redevelopment completed in 2022. The project is one of 3XN’s highest-profile international works and represents its involvement in large-scale urban regeneration and commercial architecture.

• Architectural research · 2007

  GXN research and development

  3XN’s research and development unit, established in 2007, investigates sustainable materials, green technologies, circular construction, and design products. GXN connects experimental research with the practice’s architectural projects.

• 2010Mind Your Behaviour

  Denmark · Germany

  3XN created an exhibition examining the relationship between architectural environments and human behavior. It was presented at the Danish Architecture Centre and Aedes Gallery in Berlin.

  Outcome. Exhibited in Copenhagen and Berlin.

  Source
• 2009Louisiana Pavilion

  Denmark

  GXN developed a pavilion from a specially developed biocomposite for display at the Louisiana Museum of Modern Art during the COP15 climate conference.

  Outcome. Presented as an experimental sustainable-material installation.

  Source

• 2007

  Create a dedicated research and development unitStrategy

  Background

  3XN identified materials, environmental technologies, and circular construction as areas requiring dedicated investigation alongside conventional architectural practice.

  Action taken

  The firm established GXN as a research and development department.

  Aftermath

  GXN subsequently worked on green materials, technology, circular-design principles, and product development connected with architecture.

  Source

• 1997

  Win the Muziekgebouw concert hall competitionProduct launch

  Background

  The competition provided an opportunity to deliver a major cultural project outside Denmark.

  Action taken

  3XN won the design competition for the Amsterdam concert hall.

  Aftermath

  The completed project became an important international reference for the practice and received several awards.

  Source

1. 13XNen.wikipedia.org
2. 23XN official website3xn.com