CMA’s approach to market studies and investigations

This guidance provides general information and advice on the CMA’s approach to the markets regime. It applies to how we carry out:

• market reviews
• market studies
• market investigations

The guidance is designed to give clarity to businesses and their advisors, governments, regulators, consumer groups and others, on how the regime operates and what approach we are likely to take.

Following our consultation, we have updated the guidance to:

• reflect changes to the law made by the Digital Markets, Competition and Consumers Act 2024, and changes to other legislation since the Enterprise and Regulator Reform Act 2023
• reflect recent developments in our practice, including our 4Ps framework
• consolidate our markets regime guidance documents

This guidance supersedes our older guidance, including OFT 511, OFT 519, CC3, CMA3, CMA11, and CMA136.

For market reviews, market studies and market investigations already underway before 3 February 2026, the CMA will continue to use the superseded guidance.

Read our blog post on the [update on our approach to market interventions] (add link).