Calling Yemen from the United States explained:

• 011 - US exit code; dial first for international calls made from the USA or Canada
• 967 - Country Code for Yemen
• Phone Number (may not begin with 0):
  • fixed - 7 to 8 digits, area code included
  • cell phones - 9 digits
• sample call from US to a landline in Sana'a: 011 967 1 ??? ???

How to dial to Yemen cellular:

• dialing format for calls to a cell phone: 011 967 7?? ??? ???

Area Codes:

Phone Books:

• Yellow Pages Yemen
• Tourism Yemen - an official resources publishing helpful information, including some handy local contacts