Executives are upper class. At the beginning, they work only on high positions in factories and offices but in the modern industry they will do a regular honest work. Virtually all high-density buildings need them. They require many amenities - a large number of shops and entertainment centers.
The Elites are cream of society - Gaining population - Development of a metropolis - Cities XXL - Game Guide and Walkthrough
The Elites are cream of society. They don't engage in the dirty work, they are presidents, vice-presidents, chefs, ministers and their secretaries. Advanced areas and special buildings require them. To meet all their needs is almost impossible.
You have to be constantly taking a look at Demographic statistics on the toolbar. It will show you the employment rate for the number of people available to work. It will also show you satisfaction of different domains - entertainment, trade, labor and taxes. You should take care of it, at least to about 70% to make people think they are doing well.
Maintaining a constant influx of people is not very difficult. The basic element of their satisfaction is work, so create new plots according to your plan of specialization or look at resources and try to fill up deficiencies. When new jobs are created, entrepreneurs will let you know which employees they need - then build several new housing plots.