A segment of temporary staffing that includes workers in IT/technical, engineering, accounting and finance, legal, sales and marketing, and managerial functions, among others. This segment contrasts to commercial (or traditional) staffing. While there is common consensus on how to categorize the highest and lowest skilled workers, there is a blurring of boundaries when it comes to medium skilled/middle management roles. Within these categories (such as sales & marketing, nursing, social care, and HR), what some people call professional staffing, others might call commercial staffing. Such variation exists among the categories used by different national staffing associations to estimate the size and growth of their respective markets. (See also: Specialist Staffing.)
Source: Staffing Industry Analysts