Since January 16th, 2015,
Authorized American travelers can get general licenses if they are traveling to Cuba for the following reasons:

Family visits

Official business of the U.S. government, foreign governments and certain intergovernmental organizations

Journalistic activity

Professional research and professional meetings

Educational activities

Religious activities

Support for the Cuban people

Humanitarian projects

Activities of private foundations or research or educational institutes

Exportation, importation or transmission of information or information materials

Public performances, clinics, workshops, athletic and other competitions, and exhibitions

Certain export transactions that may be considered for authorization under existing regulations and guidelines.