Today our biota is changing faster than ever before, and the trend is clearly to the loss of diversity. Systematics is the science devoted to enumerating the world biota and deciphering the relationships among its components. To work effectively and efficiently, systematists must communicate and share resources. This directory was developed and is continually being maintained as a database to serve as a resource reference for systematists worldwide, especially those who work on the insect order Diptera. The names and addresses of some 1,945 specialists in the systematics of Diptera from over 73 countries are included. Some 1,180 specialists also provided information about their interests and taxonomic speciality. "Systematics" is defined here broadly as the science of biological relationships among taxa based on characters derived from all areas, such as morphology, biochemistry, genetics, evolution, etc. The names listed here were initially derived from information provided in abstracting journals such as the BioAbstracts combined with information from questionnaires distributed at the International Congresseses of Dipterology (Budapest, 1986; Bratislava, 1990; Guelph, 1994) and mailed out with The Flyer newsletter.

In addition to this directory a list of Diptera holdings of museums, universities, and institutions world wide will be available as collection database in the tools set of the BioSystematic Database of World Diptera.

The directory is available free to all working Diptera systematists in exchange for reprints of their publications. The costs to all others is $25.00 US, payable to the S. W. Williston Diptera Research Fund of the Smithsonian Institution.