The idea behind procurement deals like the GPA and trade in services deals like the GATS is that qualified corporations from all around the world get a right to bid and perform the work, if they win. Lowering wages and spreading the profits around so that huge multinational firms get access to markets that previously were done by local business or governments with local firms.
Thats the main benefit of the agreements. On services that basically means an incremental but nonobvious process leading to the end of domestic schemes that act as a monopoly on things like healthcare, education, housing etc. and a return of market based forces, without the jobs that existed then, (like cottage industry, etc) although some services may remain subsidized until the market can work itself out, and during that period, people may need to travel for some services to afford them.
Its intent is in no small part to push wages down to global norms. (only subsidized services are subject to these rules.) For an idea of what the ideals ("best practices" are by industry check out the OECD's Services Trade Restrictiveness Index.; (STRI)
Completely free services not delivered in competition with any private entity in any way, are exempt. Water is deemed a commercial service as long as its sold. Air might not be, unless its sold. The main idea is that governments shouldn't be competing with corporations, devaluing the prices of essentials (which are deemed naturally high if the services are life saving, low if not important) stealing the food off their plates, as it were.
More money always has to buy more, and less less, as thats deemed the natural state of things. Otherwise, what would be the point of being rich! Think of the changes as a global alliance between the haves to make sure that have-ing remains the exclusive club its become, forever.
Democracy is still okay in areas that don't involve anything of economic value.
The hierarchies of global economic governance institutions is graphed out here:
http://www.levyinstitute.org/conferences/minsky2011/presentations/Wallach.pdfNote that this only applies to things which are paid money for, and all laws affecting trade in goods or services. Areas like cultural issues, (natnl. holidays, battles between various flavors of oligarchy, electoral politics, (although dont expect politicians to ever tell the truth on the power they have given away) "gay marriage" firearms, abortions, etc. military and national security, etc, are generally exempted from these rules and people and elected leaders still govern them in the old way. Often pretending to disagree to make it seem less bizarre that they never accomplish anything positive)
High value services and their provision and all government "measures" (any law, policy, rule, act or non-act, or endijng of action of entities down to the local level as well as those of quasi governmental bodies - a great many areas) "affecting" trade in services are heavily impacted. Financial services are the most impacted.
Thats where the biggest changes are happening.The corporations basically control the world now, and not figuratively, I mean actually control.