1901 – ISS was founded in Copenhagen, Denmark as a small security company with 20 night watchmen named Kjøbenhavn-Frederiksberg Nattevagt (Copenhagen-Frederiksberg Night Watch)                       

1934 – ISS entered the cleaning business with the establishment of Det Danske Rengørings Selskab A/S (The Danish Cleaning Company) as an independent subsidiary of the security company         

1946 – The first geographical expansion outside Denmark: Swedish subsidiary established

1968  – The company adopted the ISS name

1973 – Overseas expansion started 

1975  – Group revenue reached DKK 1 billion        

1977 – ISS shares listed on the Copenhagen Stock Exchange          

1989 – The total number of employees in the Group reached 100,000                       

1997 – Strategy “aim2002“ was launched. This strategy focused on Multi Services – selling a number of services to the same customer            

1999  – ISS acquired Abilis, the second largest European provider of cleaning and specialised services, in a DKK 3.6 billion acquisition, the Group’s largest ever. Abilis had about 50,000 employees and annual revenues of DKK 5.2 billion in 1998. The total number of employees in the Group reached 200,000           

2000 – A new five-year strategy “create2005“ was launched, introducing the Facility Services concept     

2003 – ISS’s first major pan-European Integrated Facility Services contract signed              

2005 – A new strategy was introduced aiming at a continuous transformation of ISS towards an Integrated Facility Services company. ISS A/S was acquired by funds advised by EQT Partners and Goldman Sachs Capital Partners, and de-listed from the Copenhagen Stock Exchange. The total number of employees in the Group reached 300,000             

2006 – Group revenue passed DKK 50 billion. ISS made the second-largest acquisition in company history, when acquiring the outstanding 51% of the shares in Tempo Services Ltd. in Australia    

2007 – Group revenue passed DKK 60 billion. ISS entered the US market through the acquisition of Sanitors Inc. The total number of employees in the Group reached 400,000     

2008 – Introduction of ISS’s strategy plan “The ISS Way”, which is built on four strategic cornerstones: customer focus, people management, the IFS strategy and a multi-local approach. ISS’s largest ever international Integrated Facility Services contract was signed       

2010 – Group revenue passed DKK 70 billion. The total number of employees in the Group reached 500,000                           

2012 – Ontario Teachers’ Pension Plan (Teachers’) and KIRKBI Invest A/S make EUR 500 million investment in ISS                                 

2013 – ISS is named world’s best outsourcing company as the International Association of Outsourcing Professionals ranks ISS as the #1 on its annual list of the world’s best outsourcing service providers – The Global Outsourcing 100.”