1.   This issue of number portability is considered an essential prerequisite to competition.

2.   And in some ways, it was nearly as revolutionary in the way it changed old habits as number portability.

3.   BT had to alter software in its U.K. network in order to accommodate number portability.

4.   Local number portability has helped, experts say.

5.   Not only does number portability allow Allegiance to let people keep their same numbers but it also lets them offer enhanced services such as caller ID and call forwarding.

6.   Number portability allows customers to switch local phone companies and keep the same phone number.

7.   Number portability, already in use in the United States, is crucial to the introduction of competition in the U.K.

8.   Number portability for the local market is expected over the next few years.

9.   Nynex, the second-biggest U.K cable communications company, claimed it is the first in the U.K. to introduce the system, called number portability.

10.   Number portability lets consumers keep their existing phone number when they switch to a different provider.