The purpose of a credentialing examination is to assure the public that individuals who work in an occupation or profession have met certain standards. To be consistent with this purpose, credentialing examinations must be job related, and this requirement is typically met by developing test plans based on an empirical job or practice analysis. The purpose of this module is to describe procedures for developing practice analysis surveys, with emphasis on task inventory questionnaires. Editorial guidelines for writing task statements are presented, followed by a discussion of issues related to the development of scales for rating tasks and job responsibilities. The module also offers guidelines for designing and formatting both mail-out and Internet-based questionnaires. It concludes with a brief overview of the types of data analyses useful for practice analysis questionnaires.