Our history

125 years, billions of experiences, one global story

From a small security company to a multinational service group...
ISS Group CEO

Kasper Fangel

"This year marks the 125th anniversary of ISS. From our beginnings as a small night-watch firm in Copenhagen, we have grown into a global leader in Integrated Facilities Services. Today, more than 325,000 dedicated employees serve over 40,000 customers across 60 markets.

And we are not done yet. ISS will continue to grow and evolve – creating more great service moments for our customers and new opportunities for people and communities worldwide. Above all, ISS is, and will always be, about people – and we will continue to make space for people and businesses to thrive."
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A story that began in Copenhagen in 1901 has grown into one of the world’s leading service organisations. From a small night watch company founded to protect the streets of the Danish capital, ISS has continually reinvented itself — guided by an entrepreneurial spirit, a commitment to people, and a belief in the power of service.
 
Over more than a century, the company has expanded across continents, navigated world events, pioneered new service concepts, and shaped the modern outsourcing industry.
 
Take a look at our journey and key milestones below.
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1901 – 1930s

From night watch to service pioneer

ISS began as Kjøbenhavn–Frederiksberg Nattevagt (Copenhagen-Frederiksberg Night Watch) on 1 April 1901, a night watch company created to protect local businesses during the early hours of the morning. Under the guidance of visionary leaders, notably C.L. David and Philip Sørensen, ISS developed rigorous professional standards, training and a focus on people, long before facility services existed as a concept.

1930s – 1945

From innovation to resilience

In the 1930s, ISS expanded beyond security with the creation of Det Danske Rengøringsselskab, establishing contract cleaning as a structured, scalable service. The company invested in training, hygiene standards and employee conditions, helping to professionalise the industry. During the German occupation, operations continued under challenging conditions marked by shortages and disruption. Despite this, ISS maintained service delivery, supported its employees and strengthened its foundations.

1945 – late 1950s

Scaling a professional service model

Following the war, ISS expanded its operations and standardised service delivery across a growing customer base. Cleaning became more structured, supported by training, clear processes and improved planning. New approaches such as night cleaning and mechanisation increased efficiency, while continued investment in employee wellbeing reinforced ISS’ people-first culture.

1960 – 1973

Accelerating international growth

ISS expanded beyond Scandinavia into new European markets, broadening its services and building a more international footprint. A more systematic and data-driven approach supported this growth. In 1968, the name International Service System, ISS, was introduced, marking a clear ambition to operate as a global service company. Rising demand for outsourced services across public and private sectors created strong momentum.

1973 – early 1980s

Creating a global organisation

In 1973, ISS was established as a unified Group, bringing together international operations under a single structure and identity. Expansion continued across Europe and into the Americas, creating scale while navigating economic challenges and increasing complexity.

1980s – 1990s

Scaling globally and strengthening the core

Growing demand for outsourcing drove expansion across Europe and beyond, supported by major contracts and acquisitions. ISS built a strong international presence across multiple regions. At the same time, the business strengthened its focus on core services, while investing in quality, training and leadership to ensure consistent delivery at scale.

2000s – 2010s

From integrated services to operational excellence

Through the create2005 strategy, ISS evolved into an integrated facility services provider, expanding beyond cleaning into catering, property and support services. This enabled more coordinated solutions that better met customer needs. ISS then strengthened service quality and consistency across its global footprint. Greater standardisation and a focus on long-term partnerships reinforced its position as a trusted global provider.

ISS today

Creating places that work, think and give

We’re one of the world’s largest facility services companies with 325,000+ colleagues in 60+ countries, creating places that work, think and give. Every day, we make our customers’ lives easier and more productive.

Shaping standards, skills and care

From employee welfare to innovation, these milestones show how ISS built a culture of care, professionalism and continuous improvement, setting the foundations for modern service excellence.
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Welfare

Gerda Buhl (right) transformed employee welfare at ISS by offering compassionate, practical support to cleaning workers. Through home visits, social counselling, access to benefits, housing help and respite holidays, she strengthened wellbeing, stability and dignity. Her legacy is a culture of care that recognised employees as people first and set new standards for workplace welfare.
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Training

Training transformed ISS in the 1940s–60s by professionalising cleaning, introducing scientific methods and modern equipment, and raising service quality. Dedicated schools, structured instruction and technical innovation empowered employees, improved efficiency and supported rapid expansion. This commitment to skills and standards helped ISS evolve from a national cleaner into an emerging international service leader.
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Standards

ISS's growth after the war enabled us to standardise methods, training and equipment across expanding operations. This consistency improved quality, efficiency and reliability, allowing services to scale nationally and internationally. Standardisation strengthened our brand, enhanced customer trust and created a unified way of working that supported rapid diversification and the evolution of modern integrated service delivery.
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Innovation

ISS has always embraced innovation – pioneering new tools, equipment and methods to make work safer, faster and higher quality. From early mechanised polishing machines to scientific cleaning techniques and modern service technologies, ISS continually led the industry, transforming efficiency and elevating standards across every service it delivered.

Meet ISS colleagues from the past...

Nightwatchman – 1901

From a small security company in 1901 to a global leader today, one thing remains the same: ISS is all about people. Back then, the night watchman’s job was to create safety for customers.
 
Today, our committed colleagues live our values, making workplaces secure, welcoming, and productive for millions around the world.
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Cleaner – 1945

Although ISS began as a security company, we became known worldwide for cleaning – and for good reason.
 
We were the first to professionalise the industry, introducing training, modern equipment, and even new job titles. Our goal? To deliver the best quality and raise the status of the profession.
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Window cleaner – 1960s

In the 60s and 70s, ISS expanded worldwide  but never lost focus on safety and quality. We created our own standards to ensure every customer experienced the same high level of ISS service, no matter where they were.
 
That commitment to quality has stayed strong for more than 100 years and we’re proud of it.
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Where will the next 125 years take us?

Wherever time takes us, ISS is proud to be an innovator, working in true partnership with our customers to build the workplaces of tomorrow and, of course, working to achieve our mission of creating space for people and businesses to thrive.
 
Help us write the next chapter of our story.
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