There are some practical hurdles to be overcome, however.

There are practical reasons why it isn't happening today, but eventually the practical hurdles will fall away.

And it would face considerable hurdles, both practical and scientific.

But skeptics question whether the two will bridge personal differences and overcome practical hurdles to forge solutions that so often eluded their predecessors.

Along the way there have been countless practical hurdles in figuring how a publicly supported university can make potentially profitable movies.

In addition, there is the practical hurdle of addressing neighborhood concerns.

And it makes paying for access to any particular site a bigger practical and psychological hurdle.

Around 1980 the lack of a coherent European strategy for development of microgravity research became an evident practical hurdle.

It is difficult to predict the future, given the practical and political hurdles than can arise.

The bigger practical hurdle is that most consumers don't have a choice of either service.