In 1997, by unanimous jury decision, the firm won the international design competition for the new Düsseldorf airport, which required a complete rebuild following a catastrophic fire. This proved another milestone contract for the firm, which had meanwhile moved its 60-strong staff into premises on Schanzenstraße in Düsseldorf Oberkassel. In the same year, they won a competition for the Stilwerk design centre Düsseldorf, which went onto receive the 2000 Association of German Architects (BDA) “Good Building” award.
 
The firm’s long-standing collaboration with the Messe Düsseldorf trade fair centre started in the late 1990s, when their design for Exhibition Hall 6 was one of the winners in a competition that attracted entries from 180 architecture firms. Over subsequent years, a number of exhibition halls were gradually modernised and refurbished according to a master plan. In 2004, Slapa Oberholz Pszczulny went on to take charge of the Messe North extension and the construction of the Esprit Arena. The Messe South building with its prestigious southern entrance between the River Rhine and the Nordpark is under construction since 2017.
 
The firm is also responsible for two other landmark buildings that grace Düsseldorf’s cityscape: the multiple award-winning GAP 15 tower on Graf-Adolf-Platz, which integrates elements of the site’s historic Post Office building, and the Spitze Speditionstraße project in Dusseldorf’s Media Harbour district, completed in 2010, which comprises the twin towers housing the upmarket Hyatt Regency Hotel, a footbridge and an office block.
 
Following the departure of H.W. Joos, in 2010 the Dusseldorf office split from the JSK Group, continuing under the new name of slapa oberholz pszczulny architekten. Since then the firm has been run by its five partners Jurek M. Slapa, Helmut Oberholz, Zbigniew Pszczulny, Wolfgang Marcour and Lothar Simonis.

With an expanding order book, including commissions ranging from the Orjin Maslak retail and office building in Istanbul and the Campustower residential development in Hamburg’s Hafencity to a new terminal for Munich airport, a growing workforce and the creation of new departments, sop architekten finally outgrew their office on Karl-Arnold-Platz. In 2019 the architects, interior designers and construction managers of sop architekten all moved to new premises on Emmericher Straße that housed its various departments and a model-making workshop on the same site.

To guarantee the architectural quality of its work, project managers, partners and staff meet regularly at each stage of a project, involving experienced professionals alongside their younger colleagues. This ensures that the firm’s distinctive signature style, which has been rewarded with numerous BDA and other architectural awards, is passed on to individual project teams. A more dynamic corporate structure and the recruitment of Bjørn Polzin as a new executive director help to maintain these high standards going forward.

1987
J. M. Slapa and H. W. Joos set up Architekturbüro JSK Düsseldorf

1988
H. Oberholz and Z. Pszczulny become partners in JSK Düsseldorf

1992               
J. M. Slapa, H. Oberholz and Z. Pszczulny become shareholders of the JSK Gruppe, Frankfurt, Braunschweig, Berlin. JSK Düsseldorf goes on to complete material to the following projects:

Airport Terminal 2, Frankfurt/Main (1996)
Fort Malakoff Park Business Centre, Mainz (1997)
Hyatt Regency Hotel, Mainz (1998)
Düsseldorf International Airport (2001, 1st price 1997)
Stilwerk, Dusseldorf (2001, 1st price 1997)
Hohenzollernwerk, Dusseldorf (2003)
Broker Office Center, Frankfurt (2004)
Bahnhof Messe/Arena, Dusseldorf (2004)
Esprit Arena Düsseldorf (2004, 1st price 1998)
Northern Entrance + Northern Extension Messe Düsseldorf (2004-2010)
Messe Düsseldorf Regeneration (2004-2010)
Gap 15 Tower, Dusseldorf (2005, 1st price 2002)
EON Ruhrgas, Essen (2007, 1st price 2006)
Kö 18, Dusseldorf (2008)
DEG Corporate Headquarters, Cologne (2008)
Hoberg & Driesch Logistics Centre, Dusseldorf (2008)
Hafenspitze, Dusseldorf (2010, 1st price 2000)

2010               
The firm leaves the JSK Group and continues under the name slapa oberholz pszczulny,
sop | architekten. Shareholders Z. Pszczulny and M. Rutz take over JSK Architekci (Poland). The two firms work together on various projects.

Since then sop | architekten have completed the following projects:

UEFA Stadium Breslau (2011, 1st price 2007)
Copernicus Airport, Breslau (2011)
La Cour Vivaki, Dusseldorf (2012)
Orjin Maslak, Istanbul (2014)
Vallourec Head Office, Dusseldorf (2013)
Dusseldorf Airport Authority Headquarters (2014, 1st price 2012 in a bidding process)
Belsenpark Office Complex, Dusseldorf (2015)
Clara und Robert, Dusseldorf (2015)
Academic and laboratory buildings, Bergische Universität Wuppertal (2017, 1st price 2011)
DEG Campus, Cologne (2017)
Zooviertel Carrée, Dusseldorf (2017)
Andreasquartier, Dusseldorf (2017, 1st price 2008)
Equilo, Cologne (2017)
Goldbeck Corporate HQ, Bielefeld (2017, 1st price 2015)
Quartier Neuss Weckhoven, Neuss (2018, 1st price 2012)
CT² Center for Teaching and Training, RWTH Aachen Campus (2018)
KVBW HQ Building, Karlsruhe (2018, 1st price 2014)
trivago Headquarters, Dusseldorf (2018)
Borussia Park 8 Grad, Mönchengladbach (2018)
Campustower Apartment Block, Hafencity Hamburg (2018, 1st price 2014)
Textilakademie, Mönchengladbach (2018)
Neue Messe Essen (2019, 1st price 2012)
Fürst & Friedrich, Düsseldorf (2019)
Neue Messe Süd, Düsseldorf (due to complete 2019/20)