Extend this out to the 30% of jobs which require such licenses and you can see that there will be something of a cooling effect on labour mobility.

FORBES: A Use For The Commerce Clause: Increasing US Labour Mobility Through Occupational Licensing

And as such licensing is often State, rather than nationally, based this will have the effect of reducing that labour mobility.

FORBES: A Use For The Commerce Clause: Increasing US Labour Mobility Through Occupational Licensing

In fact, they can have the opposite effect and insulate lower classes from upward mobility.

CNN: Reduce poverty by promoting schools, families

The Association of School and College Leaders (ASCL) said the proposals would not improve social mobility and would have a "damaging effect" on pupils from the most deprived areas.

BBC: Academies could give priority on places to poorest

He said the "right to move" was just an idea at the moment but he would pass a law bringing it into effect if the other measures did not succeed in increasing the mobility of tenants.

BBC: Social tenants in England to get wider home swap choice