Computed tomography colonography (CTC) is emerging as an alternative to conventional colonoscopy (CC). However CTC is not yet in widespread use due in part to the lack of suitably trained radiologists. We have developed a novel remote access system to train radiologists for colorectal cancer screening using CTC. To ensure that radiologists can gain the relevant experience without the need for any specialist equipment or software, we opted for designing a system that is accessible via the Internet using a standard browser. The interface lets the user locate and characterise polyps with the help of appropriate tools such as windowing, polyp measurement, zooming and a 3-D view. Each user has an account in order to allow monitoring of their training. They can also run an automatic evaluation of their work based on gold standard information previously gathered from specialists. This thesis also describes an initial implementation exclusively made up of Java Servlets. The evaluation of this system has been discussed in order to determine a better approach. The final system has been developed using a combination of Java Servlets and Applets. This approach offers fast response time to the user-interface. An iteration of lumen tracking using the system takes approximately 45 seconds. This research has yielded an operational system that meets the needs of remote access users.