Whenever there is a collectivity of people with structures, tasks and interphases between people and systems there are some individuals who by choice or by the need of the hour or situation become consultants, advisors, experts and problem-solution givers. This paper examines how consultants emerge, are seen, what roles they undertake in organizations, what factors influence the consultant's roles and what are the new definitions and dimensions of a consultant's role. It identifies the context in which an organization and the consultant interphase. It states the different phases of evolution of organization growth and how the role of a consultant changes. These dimensions are discussed based on experiences of many consultants and existing literature. Most of the role descriptions are borrowed from existing literature and from experiences and discussions with consultants and industrialists. In the Indian context due to constant flux and transition, consultants have to review and define an appropriate role for themselves to contribute to the design and development of institutions and formal work organizations.