What are the qualities of a Good Questionnaire ?

Hi All,

Background:

“…customers from their traditionally passive role as receivers of marketing communications, gives them much greater control over the information search and acquisition process, and allows them to become active participants in the marketing process.”  The discovery of digital technology has redefined the relationship between companies and consumers. Companies have variety of digital channels of marketing their products and services to consumers; emails, blogging, forum, newsletters, pop-ups, Bluetooth advertisement, mobile phone and iTV are used in digital marketing. Never have consumers so much products/services information available to them, leaving them with much power to decide the success or failure of product or service.

This array of digital channels, which marketers are chosen because of cost effectiveness, have also created problem for businesses on how the to efficiently and effectively integrate these into their marketing strategies. This research seeks to study digital marketing trends from customer prospective. Then customers (B-to-B and B-to-C) responses to different digital marketing channels will be study and documented; leading to guideline or mini-frame work that will help marketing mangers make informed choice on type/s digital medium to adapt verses cost factor.

Please advise me on how to draft a questionnaire for my project "Digital Marketing, Customer's Prospective".
What is a good Questionnaire ?

Thank you,

Gnexplore