Personal computer (PC) driven digital imaging devices are now becoming available in the market place for use in radiation oncology to produce what are known as real time portal images. These limited contrast images are used to verify the patient anatomy under treatment by megavoltage x-rays and are a vital part of the patient treatment. The current generation of devices can produce both single and movie loop images in real time for physician review and approval. To disseminate these images and other digital images used in the planning and delivery of radiation therapy, a PC-based picture archiving and communications system has been developed that is tailored to the special needs of radiation oncology.