Mutuality of obligation, without the jargon
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Mutuality of obligation (MOO) is the test that asks: must the client offer ongoing work, and must you accept it? Employment presumes both; a contract for services typically has neither beyond the signed project.
The two levels
- Between engagements: must they find you work when a project pauses? If yes, that's employment-shaped. If the contract simply ends, it isn't.
- During the engagement: can they hand you any task they like, or only the contracted deliverables? Scope-locked is outside-shaped.
Why it rarely decides alone
Almost every contractor engagement has an obligation to pay for work done — tribunals therefore treat MOO as a tiebreaker that amplifies the control and substitution findings rather than a standalone winner. Contract clauses denying MOO help, but courts look at what happened in practice.
What to check in an offer
Fixed-term with defined deliverables and no "such other duties as required" clause is the outside-friendly pattern. Indefinite "ongoing support" arrangements are the opposite. Compare real examples on the board — every listing carries the status evidence the agency itself published.
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