Consultancy (noun)

1. The provision of expert advice or professional services by a consultant or group of consultants.
2. A company or organization that provides expert advice or professional services in a particular field.

Origin:

Early 20th century: from consultant + -cy.

Examples:

1. He has a successful consultancy firm that provides expert advice to businesses.
2. She works for a consultancy company that specializes in human resources.
3. The consultancy is providing expert advice on how to improve the company's efficiency.
4. The consultancy firm is specializing in providing professional services in the field of marketing.
5. The consultancy services are aimed at helping the client achieve their goals.