When IAU Symposium No. 17, the most recent international conference on visual double stars to take place in the United States, was held in Berkeley in 1961, there was little discussion on observational techniques and no introductory remarks were presented on the subject. The reasons for this are obvious. The classical techniques of double-star observation, those that provided virtually all the data available on visual double stars, were too well known to require introduction or discussions; other methods, with the possible exception of early image tube and electronic camera experiments, did not exist.
Today, more than ten years later, most double-star work continues to be carried out by the same classical techniques. However, several methods have come into use or have recently been developed that are capable of contributing importantly to visual double-star research.