The Competition and Markets Authority (CMA) has issued letters as a follow-up to its housebuilding market study report. The letters are likely aimed at addressing any potential competition concerns identified in the report. This action indicates that the CMA is actively monitoring the housebuilding sector for compliance with competition law. The affected businesses are likely the housebuilding companies mentioned in the report, and the implications for other companies in the industry could include increased scrutiny and potential enforcement actions.