This document discusses consulting and provides definitions and types of consultancy. It defines consulting as providing objective advice to help organizations improve performance through analyzing problems and developing improvement plans. The consulting industry has seen significant growth and increasing competition. There are three main types of consultancy: internal consultants who are organization members and report internally; external consultants from outside the organization who provide direct, unbiased perspectives; and external-internal hybrid consultants. The document compares advantages and disadvantages of internal and external consultants in serving organizations.