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Examples of professional services include those of: accountants, actuaries, appraisers, architects, attorneys, business consultants, business development managers, copywriters, engineers, funeral directors, law firms, public relations professionals, recruiters, researchers, real estate brokers, translators and medical centres. While not limited to licentiates (individuals holding professional licenses), the services are considered[by whom?] "professional" and the contract may run to partnerships, firms, or corporations as well as to individuals.
Defining professional services firms 
Many industrial groupings have been used for academic research when looking at professional services firms, making a clear definition hard to attain. Some work has been directed at better defining professional service firms. In particular, Von Nordenflycht generated a taxonomy of professional service firms, defining four types:
- Classic PSFs (e.g. law and accounting firms) - characterised by a high knowledge intensity, a professionalised workforce, and low capital intensity
- Professional campuses (e.g. hospitals) - characterised by a high knowledge intensity, a professionalised workforce, and high capital intensity
- Neo-PSFs (e.g. management consultants) - characterised by a high knowledge intensity and a low capital intensity
- Technology developers (e.g. R&D firms, biotechs) - characterised by a high knowledge intensity and a high capital intensity
Frameworks such as this greatly aid the ability of managers and academics to better understand how such firms manage themselves and how to judge benchmark practices.
The selection of an independent contractor or consultant providing professional services usually depends on skill, knowledge, reputation, ethics, and creativity. Prices for services, even within the same field, vary greatly. Some professional-service providers are able to give fixed rates for projects, while others define the price only after assessing the work involved. For this reason, it is common to hire professionals on the basis of an hourly fee and of an estimated length of project (scope).
In the past, independent contractors for professional services were located and hired by various means, including recommendation and directories (e.g. yellow pages). The popularity of the Internet has led to a new crop of professional-services sites that allow independent contractors to offer their services to a larger audience, while allowing individuals or companies to find professionals quickly and easily.
Professional-services employees 
The term "professional services" is also used frequently by corporations such as banks and retailers that offer infrequent or ongoing services for their customers.
See also 
- Von Nordenflycht, A, "What is a professional service firm? Toward a theory and taxonomy of knowledge-intensive firms", Academy of Management Review, Vol. 35, No. 1. (2010), pp. 155-174