A lawyer, according to Black's Law Dictionary, is "a person learned in the law; as an attorney, counsel or solicitor; a person who is practicing law." Law is a system of rules and guidelines which are enforced through social institutions to govern behavior. Working as a lawyer involves the practical application of abstract legal theories and knowledge to solve specific individualized problems, or to advance the interests of those who retain (i.e., hire) lawyers to perform legal services. The role of the lawyer varies significantly across legal jurisdictions, and so it can be treated here in only the most general terms.

Historically lawyers in most European countries were addressed with the title of doctor, and countries outside of Europe have generally followed the practice of the European country which had policy influence through colonization. The first university degrees, starting with the law school of the University of Bologna (or glossators) in the 11th century, were all law degrees and doctorates. Degrees in other fields did not start until the 13th century, but the doctor continued to be the only degree offered at many of the old universities until the 20th century. Therefore, in many of the southern European countries, including Portugal and Italy, lawyers have traditionally been addressed as "doctor," a practice which was transferred to many countries in South America and Macau. The term "doctor" has since fallen into disuse, although it is still a legal title in Italy and in use in many countries outside of Europe.

The title of doctor has never been used to address lawyers in England or other common law countries (with the exception of the United States). This is because until 1846 lawyers in England were not required to have a university degree and were trained by other attorneys by apprenticeship or in the Inns of Court. Since law degrees started to become a requirement for lawyers in England, the degree awarded has been the undergraduate LL.B. In South Africa holders of a law degree who have completed a year of pupillage and have been admitted to the bar may use the title "Advocate", abbreviated to "Adv" in written correspondence.

Even though most lawyers in the United States do not use any titles, the law degree in that country is the Juris Doctor, a professional doctorate degree, and some J.D. holders in the United States use the title of "Doctor" in professional and academic situations.

In countries where holders of the first law degree traditionally use the title of doctor (e.g. Peru, Brazil, Macau, Portugal, Argentina, and Italy), J.D. holders who are attorneys will often use the title of doctor as well. It is common for English-language male lawyers to use the honorific suffix "Esq." (for "Esquire"). In the United States the style is also used by female lawyers.