Background: Our group has shown that real-time teleultrasound consultation is not only technically feasible, but also offers diagnostic and management modifications in the clinical setting [1,2]. It helps to bridge the health care gap between the city and the country, where access to subspecialists is usually difficult. Majority of telemedicine work around the world is currently performed with ISDN connection, which is still relatively costly, and is limited to larger centers where ISDN access is available. Rapid evolution of technology has enabled Internet technology to be available to most corners of the world, and the cost of using IP networks is rapidly reducing. Purpose: To compare the quality of real-time ultrasound images transmitted via the IP network vs. ISDN lines. Methods: ISDN and/or IP (broadband wireless local multipoint distribution service, AAPT) connections between three Queensland Hospital sites were established. A standard ultrasound videotape containing fetal images from three different trimesters of pregnancy was played to four experienced observers at random using either ISDN or IP connections at various bandwidths. The observers were blinded to the network or bandwidths used, and evaluated the quality of the images with a standard seven-point scoring sheet on 30 fetal anatomic landmarks. Results: A total of 12 evaluations were performed for various combinations of bandwidths and networks. The intra- and interobserver variations were not significant. The most significant variable affecting the mean score was the bandwidth used. The mean score for transmission using IP was about 0.5 points lower than that using ISDN linkage across all the different bandwidths, but the differences did not reach statistical difference (P = 0.06). Conclusion: IP connection is a reasonable alternative to ISDN linkage for real-time teleultrasound transmission. It has enormous potential to expand telemedicine applications to more remote sites at lower cost, and further explorations as to its reliability and limitations should be performed.