The 2001 Winter Internet Survey was conducted as a collaboration between the Internet Survey of American Opinion research project at the California Institute of Technology (R. Michael Alvarez, Robert Sherman, Carla VanBeselaere and Catherine Wilson) and the USCCaltech Center for the Study of Law and Politics (R. Michael Alvarez, Ann Crigler, Jonathan Katz, D. Roderick Kiewiet, Timur Kuran, and Edward J. McCaffery). This survey was conducted from March 22, 2001 for approximately three weeks. This documentation begins with a presentation of the survey design and protocol, most importantly including a discussion of subject recruitment for the internet survey. The section following is a detailed codebook describing the dataset. Attached as appendices are copies of the respondent information questionnaire and the winter survey.