Specialists are citizens of your cities which, instead of trudging in the fields and mines around the cities, dedicate themselves to more refined work in your special buildings' specialist slots. Despite the fact that in this way less land is being taken advantage of, Specialists are very important for your civilization, because they are the main source of 
Great People Points (GPPs) and are thus central to your Great People generation! For more info on that, visit this article.
Specialists are divided into several types, depending on the building they're assigned to. Besides certain types of GPPs, each type will also produce some stat - 
Production, 
Gold, 
Culture or 
Science. The stat they produce is added to the base production of the city, and is thus subject to enhancement bonuses.
Specialists are crucial for your Great Person generation, being the most important contributor to that end. If you want a certain Great Person generated, assign Specialists of the relevant type in your cities. But aside from that, Specialists produce valuable stats which aren't usually available in the land (especially Culture and Science). Use them to enhance these sides of your empire's stat generation, particularly in cities that contain bonus buildings for the relevant stat.
Despite that 
Unhappiness from specialists is shown separate to unhappiness from the rest of the population, specialists produce no more Unhappiness than any other 
Citizen, and can even produce less with the right enhancers.
Specialist Enhancers
| Enhancer | Effect |
|---|---|
 Statue of Liberty
|
+1 Production from Specialists (including  Unemployed) in every city.
|
 International Space Station
|
+1 Production from Scientists and +1 Science from Engineers
|
| Template:SocialPolicy5 | +2 Science to each specialist.
|
| Template:SocialPolicy5 | Specialists produce half the normal amount of Unhappiness. (only in vanilla and Gods & Kings; Freedom Ideology Tenet in Brave New World)
|
| Template:SocialPolicy5 | Specialists consume only half the normal amount of  Food, 1 instead of 2. (only in vanilla and Gods & Kings, Freedom Ideology Tenet in Brave New World)
|
Artist Artist
Artist (Vanilla and Gods & Kings)
+3 Culture
+3 Great Artist points
| Building | Specialists |
|---|---|
 Temple
|
 Artist Artist (only in vanilla)
|
 Mud Pyramid Mosque
|
Artist Artist (only in vanilla)
|
 Museum
|
Artist Artist (only in vanilla and Gods & Kings)
|
 Opera House;  Ceilidh Hall 
|
Artist (only in vanilla and Gods & Kings)
|
 Cathedral
|
Artist (only in Gods & Kings)
|
 Amphitheater
|
Artist (only in Gods & Kings)
|
Artist (Brave New World)
+3 Culture
+3 Great Artist points
In the Brave New World expansion pack, the Artist specialist has been split into three new kinds of Specialists: Writer, Artist and Musician. All of the cultural buildings providing slots for the former Artist Specialists have been altered - they now provide Great Work slots instead. Similarly, all Wonders that used to provide Great Artist points have now been altered to provide Great Work slots of the three types.
Only the three Guilds now provide slots for Specialists, as well as GPPs towards the specific Great Person:
| Building | Specialists |
|---|---|
 Artists' Guild 
|
Artist Artist
|
Musician
+3 Culture
+3 Great Musician points
| Building | Specialists |
|---|---|
 Musicians' Guild
|
Musician Musician
|
Writer
+3 Culture
+3 Great Writer points
| Building | Specialists |
|---|---|
 Writers' Guild
|
Writer Writer
|
Engineer Engineer
+2 Production
+3 Great Engineer points
| Building | Specialists |
|---|---|
 Workshop;  Longhouse
|
Engineer
|
 Windmill;  Coffee House
|
Engineer
|
 Factory
|
Engineer Engineer
|
Merchant Merchant
+2 Gold
+3 Great Merchant points
| Building | Specialists |
|---|---|
 Market;  Bazaar
|
 Merchant
|
 Bank;  Satrap's Court;  Hanse
|
Merchant
|
 Stock Exchange
|
Merchant Merchant
|
Scientist
+3 Science
+3 Great Scientist points
| Building | Specialists |
|---|---|
 University;  Wat
|
|
 Public School
|
|
 Research Lab
|
|
Unemployed Unemployed
+1 Production
In a few ways, Unemployed citizens behave as specialists. They do not work a tile, and receive the bonus from the Statue of Liberty, as though they were specialists, but receive no other specialist bonuses[Verify. True for Secularism.] and produce little benefit. The number of slots for Unemployed citizens is unlimited.
Notes
Added in the Gods & Kings expansion pack.
Added in the Brave New World expansion pack.