This document consists of four symposium papers each providing a critical examination of a particular data collection technique in vocational education research. Texts of the following presentations are provided: "Mail Survey Research," by Betty Heath-Camp; "The Telephone Interview as a Data Collection Technique," by James P. Key; "The Personal Interview as a Data Collection Technique," by Maureen E. Kelly; and "The Audio Cassette Tape as a Data Collection Technique," by Ismail bin Yahya. (MN)