Licensing & regulation
What is the SIA Approved Contractor Scheme (ACS)?
The Approved Contractor Scheme is a voluntary SIA scheme assessing security suppliers against a standard covering their management, processes and staff. Approved contractors gain operational benefits alongside the accreditation.
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<img src="https://secureoptix.co.uk/glossary/approved-contractor-scheme/diagram.svg" alt="Approved Contractor Scheme — diagram from SecureOptix" width="880" height="620" loading="lazy">
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<a href="https://secureoptix.co.uk/glossary/approved-contractor-scheme">What is the SIA Approved Contractor Scheme (ACS)?</a> — diagram by
<a href="https://secureoptix.co.uk">SecureOptix</a>
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</figure>It assesses the business rather than the individual. Where a licence says a person may work, ACS approval says a firm is run to a defined standard — how it recruits, screens, deploys, supervises and improves.
Its practical benefit is the ability to deploy a proportion of staff who have applied for a licence but not yet received it, which matters enormously in an industry with constant turnover and mobilisation deadlines.
It is assessed periodically and scored, and many client tenders require it. Losing approval is therefore a commercial event, not only a compliance one.
What goes wrong in practice
- Approval treated as a certificate rather than as a standard that has to be evidenced continuously.
- Licence dispensation used beyond the permitted proportion.
- Assessment preparation done in the weeks beforehand, which the scoring is designed to detect.