For the first 20 years, there were some difficulties and obstacles in our bilateral relations.

WHITEHOUSE: The White House

As we move towards the relaunch of these negotiations tomorrow, we recognize the difficulties, challenges and obstacles that lie ahead.

WHITEHOUSE: Middle East Peace Talks

Resistance to genetically modified foods, technical difficulties, legal and business obstacles and the ability to develop improved foods without genetic engineering have winnowed the pipeline.

FORBES: The Rationalist

Sprint network chief Bob Azzi said his crews were working feverishly to improve service in New York despite multiple obstacles, including difficulties getting into Manhattan and trouble accessing rooftop antennas.

WSJ: Outages Expose Wireless Carriers' Backup Plans