Field tests were conducted to assess the effectiveness of American Biophysics Counterflow 2000 (CF2000) traps compared to CO2-baited Centers for Disease Control (CDC) miniature traps at a site in central Sweden. Adult mosquitoes representing 17 species and 6 genera were collected in July and August 1998. Although the 2 trap types did not differ significantly in total number of adult female mosquitoes collected, CF2000 traps captured a greater diversity of mosquito species and significantly more adult males than did CDC traps. Interspecific differences in capture rates and interactions between trap type and location also were observed.