Paper-based postal questionnaires
The most common form of questionnaire is the paper-based, printed instrument. The most typical forms of distribution are by post, handing them to individuals at group events or leaving them in a prominent position where people are encouraged to complete and return them to the distribution point. The latter of these is by far the least successful, as you can imagine. Postal questionnaires are the most costly as you will have to enclose a stamped addressed envelope in each for return; you will also be relying heavily on the willingness of the respondent to complete and return the questionnaire. Distributing paper questionnaires to a group when they are gathered together in a particular location is usually the most successful approach.