4. Douglas County, CO
Towns include: Castle Rock, Lone Tree, Parker, Stonegate
Job growth (2000-2010): 64.5%
Perched between Colorado`s two largest cities, Denver and Colorado Springs, this county is all about big business. Six Fortune 500 companies are based here, including major employers like Liberty Media, the Dish Network and Sprint Nextel.
Attracted by a great tax rate, a highly educated workforce and some of the most beautiful country on any side of the Rockies, more companies are moving to Douglas County and bringing jobs. In June, thermoplastics maker Gordon Holdings said it plans to relocate here, adding 240 jobs. Meanwhile, insurer CNA opened its western service center here, bringing 300 new positions with it.
15. Wake County, NC
17. Sarpy County, NE