More about security services

NSI approved companies provide a wide range of security services including security guarding, door supervision, event stewarding, private investigation, cash and valuables in transit, key holding, CCTV operation, security dog services, close protection and covert services.

Those approved companies operating in the licensable sectors of security guarding, key holding, cash and valuables in transit, door supervision, public space surveillance CCTV and close protection must hold an appropriate SIA licence. 

Prior to commencement of a service, your selected NSI approved company will conduct a full site survey in accordance with recognised standards to define your particular security, health and safety requirements.

Assignment instructions for all duties will be formulated in full consultation with you. These will specify the prime objective of deployed security staff clearly linked to your management Policy and strategy. Where a management Policy and strategy does not exist the security objectives will be defined based on an agreed approach to safeguarding your property and assets.


Search the NSI Company Finder or ask your NSI approved company for sight of their unique Certificate of Approval for the specific services for which they are approved by NSI.

Guarding services

Every NSI approved company offering door supervision, cash in transit, key holding, close protection, public space surveillance CCTV and security guarding, must ensure their operatives SIA licenses are up to date.

An operative's SIA licence must be displayed at all times when on duty, so don’t hesitate to ask to see the licence if it is not visible. You can also check here to make sure the individual is on the register of licence holders on the SIA website.


NSI guarding companies are committed to:

At least twice yearly, independent, expert compliance audits

NSI Guarding Gold companies operate a Quality Management System

Compliance with British and international standards including ISO 9001

Screening every employee as required

Demanding adherence to the Provision of Labour in the Security and Events Sectors (NCP 119) across their supply chain

The company you choose may be part of the SIA's Approved Contractor Scheme. This is increasingly becoming the minimum requirement for buyers of security services.

Learn more about security for your workplace

Security Guarding

Keyholding and Alarm Response Services

Door Supervision

Event Stewarding

Transport of Cash and Valuables

Security Dog Handling Services

More About Security Systems

Learn more about fire safety for your workplace

More About Fire Safety

NSI Gold and Silver Medals - Signifying a companies approval with NSI

Look out for the NSI hallmark

It’s the most widely recognised mark of approval in security and
fire safety. NSI approval tells you the company is:


Technically Competent

Working to International and British Standards and NSI Codes of Practice, teams have relevant technical experience


Gold approval - operating a Quality Management System to ISO 9001 and NSI Quality Schedules


Reputable Directors & leaders with relevant business experience and effective employee security screening

Find an NSI approved company