Market Investigations Ltd v Minister for Social Security [1969] 2 QB 173 is a UK labour law case which was heard as a challenge to a decision by the Government that employed National Insurance contributions were due on the payments to the worker.

[1] In some regards this judgement appears to undermine the three-step reasoning in Ready Mixed Concrete (South East) Ltd v Minister of Pensions and National Insurance (RMC), which was decided the previous year.

There was a dispute between the business for whom she did the surveys, Market Investigations, and the Minister for Social Security, over whether National Insurance contributions should have been made on her behalf.

He found that there was nothing in the case which showed that the contracts were made with Irving, as a person in business on her own account, and therefore the decision based on control was sound.

In doing so it obscured the importance of the 'right of control' to Cooke, J's decision, giving prominence to the later review of whether Irving provided her services as a person in business on her own account.