Joint employment arises where two entities each exercise sufficient control over the same worker. Both may then be liable for wage, discrimination and labour obligations.

Where it appears. Staffing agencies and their clients; franchise relationships; subcontracting and vendor arrangements; and parent-subsidiary structures with shared management.

Tests. Formulations differ by statute and have shifted with successive rulemaking. Recurring factors include the power to hire and fire, supervision and control of schedules and conditions, determination of pay rate and method, maintenance of employment records, and control over the work performed.

Wage liability is typically joint and several, meaning the client pays if the staffing agency does not — including for overtime aggregated across hours worked for both.

Discrimination and harassment. A client that supervises staffing agency workers can be liable for harassment in its workplace and for discriminatory removal from an assignment.

Contractual protection is partial. Indemnities and insurance requirements allocate loss but do not prevent liability, and are worth only the counterparty’s solvency.

Practical controls. Avoid directly disciplining, scheduling or setting pay for another entity’s workers where the commercial arrangement permits; require proof of the agency’s wage and insurance compliance; and audit periodically.