They are an important barrier to the movements of air masses.

They were the most important barrier between her and Ebola.

There are at least two important barriers to this enterprise within Western culture.

Under the law, parents are an important barrier to coercion of minors.

Legal issues relating to this area also represent an important barrier.

The business strategies of operators also create important barriers to increased usage.

Six percent is an important psychological barrier and going through it ought to make investors worry more in the near term about the stock market.

Market experts said the $30 level was an important barrier.

The close was still lower than Monday's final finish of 19,837.16 - the first drop below the psychologically important 20,000 barrier in five years.

We agree that there are important barriers to integration of retail financial services markets.