In what circumstances would I need to submit an employment intermediary report?

If a personal service company supplies more than one worker, including themselves or any subcontractors, it may need to submit an employment intermediary report.
Legislation introduced in April 2015 requires an intermediary or agency to submit an employment intermediary report every 3 months for any person they place into an assignment. An intermediary is any person who makes arrangements for an individual to work for a third party or who pays an individual for work done for a third party.

If a personal service company supplies more than one worker, including themselves or any subcontractors, it is considered to be acting as an intermediary. If that worker is not paid through PAYE the company will need to ensure it complies and sends a report to HMRC disclosing details about the worker for each reporting period. 

Amy FowlerIn what circumstances would I need to submit an employment intermediary report?