Here's how you can write off these expenses:

The main purpose of your trip is business related (Ex:  convention / client meetings /  business research)

If the main point of the trip is business, and you spend LESS than one week out of the US, all of your travel expenses are deductible

If the main point of the trip is business , you spend MORE than one week out of the US, and at least 76% of your time spent is business related, then all of your travel expenses are deductible.

Travel expenses can include:

• Plane tickets

• Hotels

• Meals While Traveling

• Car Rentals

• Train Tickets

Solid documentation about time spent and expenses paid is really important.  

If you have questions, please let me know.