Steve Turner, a spokesman for the Home Builders Federation, says the planning system has been an obstacle for growth for years.

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The U.S. visa system is the single biggest obstacle in attracting more international tourists.

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But the first-past-the-post voting system for MPs is a huge obstacle for any small party.

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Tissue cloned in this way from the patient's own cells would not, it is thought, be rejected by the body's immune system, which is currently a major obstacle to organ transplants and many other treatments.

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It is true that many biases still exist, but perhaps the most difficult obstacle for women lies within our own belief system.

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Once at the motor sports complex, journalists took turns testing all-wheel-drive XJs and smaller XFs, which also get the system as an option for 2013, by flinging them through various obstacle courses, every one of which was covered in several inches of snow with thick ice underneath.

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But depending on a child's support system, Oliker doesn't think an absent father is necessarily an obstacle.

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The vehicle has a built-in safety system that uses lasers and three-dimensional models of its surroundings to navigate obstacle-strewn warehouses.

FORBES