ISO 15189 is a standard

that sets out the requirements for a quality management system specifically for medical laboratories. It is intended to help medical laboratories to provide accurate and reliable test results, and to enhance customer satisfaction through the effective application of the system, including processes for continuous improvement.

A consultancy is a company or individual that provides expert advice, guidance, or assistance to businesses or organizations in a particular field or area of expertise. In the case of ISO 15189, a consultancy could provide support to a medical laboratory in the process of implementing and maintaining a quality management system that meets the requirements of the standard. This could include helping the laboratory to understand the requirements of the standard, providing guidance on how to effectively implement and document the system, and assisting with the process of obtaining accreditation to the standard.