Consulting in a Nutshell

Consulting is the provision of expertise to clients who require a particular type of knowledge or service for a specific period of time, thus providing an economy to the client. Businesses implementing a major project may need additional experienced staff to assist with increased work during that period.

There appear to be 3 major facets to consulting:
1) subject matter expertise i.e. C#, .NET, database administration
2) industry expertise i.e. applying the skills to a particular problem
3) consultancy skills i.e. delivering the product of 1 + 2 in the client environments